diff --git a/__tests__/fixtures/anaconda-test-detailed-export-v4.json b/__tests__/fixtures/anaconda-test-detailed-export-v4.json
index 65893b57..32d622cf 100644
--- a/__tests__/fixtures/anaconda-test-detailed-export-v4.json
+++ b/__tests__/fixtures/anaconda-test-detailed-export-v4.json
@@ -310,7 +310,7 @@
     "unladenRange": 18.74,
     "yaw": 10,
     "fullTankRange": 18.36,
-    "hardness": 170,
+    "hardness": 65,
     "ladenRange": 16.59,
     "unladenFastestRange": 74.2,
     "ladenFastestRange": 66.96,
diff --git a/src/app/components/AvailableModulesMenu.jsx b/src/app/components/AvailableModulesMenu.jsx
index fba8ad15..1d3df29c 100644
--- a/src/app/components/AvailableModulesMenu.jsx
+++ b/src/app/components/AvailableModulesMenu.jsx
@@ -1,4 +1,5 @@
 import React from 'react';
+import * as ModuleUtils from '../shipyard/ModuleUtils';
 import { findDOMNode } from 'react-dom';
 import TranslatedComponent from './TranslatedComponent';
 import { stopCtxPropagation } from '../utils/UtilityFunctions';
@@ -213,7 +214,14 @@ export default class AvailableModulesMenu extends TranslatedComponent {
     for (let i = 0; i < sortedModules.length; i++) {
       let m = sortedModules[i];
       let mount = null;
-      let disabled = m.maxmass && (mass + (m.mass ? m.mass : 0)) > m.maxmass;
+      let disabled = false;
+      if (ModuleUtils.isShieldGenerator(m.grp)) {
+        // Shield generators care about maximum hull mass
+        disabled = mass > m.maxmass;
+      } else if (m.maxmass) {
+        // Thrusters care about total mass
+        disabled = mass + m.mass > m.maxmass;
+      }
       let active = mountedModule && mountedModule.id === m.id;
       let classes = cn(m.name ? 'lc' : 'c', {
         warning: !disabled && warningFunc && warningFunc(m),
diff --git a/src/app/components/Defence.jsx b/src/app/components/Defence.jsx
index 7d6f5e78..545e6eac 100644
--- a/src/app/components/Defence.jsx
+++ b/src/app/components/Defence.jsx
@@ -61,50 +61,90 @@ export default class Defence extends TranslatedComponent {
     const shieldSourcesData = [];
     const effectiveShieldData = [];
     const shieldDamageTakenData = [];
-    const shieldTooltipDetails = [];
-    const shieldAbsoluteTooltipDetails = [];
-    const shieldExplosiveTooltipDetails = [];
-    const shieldKineticTooltipDetails = [];
-    const shieldThermalTooltipDetails = [];
+    const shieldSourcesTt = [];
+    const shieldDamageTakenAbsoluteTt = [];
+    const shieldDamageTakenExplosiveTt = [];
+    const shieldDamageTakenKineticTt = [];
+    const shieldDamageTakenThermalTt = [];
+    const effectiveShieldAbsoluteTt = [];
+    const effectiveShieldExplosiveTt = [];
+    const effectiveShieldKineticTt = [];
+    const effectiveShieldThermalTt = [];
     let maxEffectiveShield = 0;
     if (shield.total) {
       shieldSourcesData.push({ value: Math.round(shield.generator), label: translate('generator') });
       shieldSourcesData.push({ value: Math.round(shield.boosters), label: translate('boosters') });
       shieldSourcesData.push({ value: Math.round(shield.cells), label: translate('cells') });
 
-      if (shield.generator > 0) shieldTooltipDetails.push(<div key='generator'>{translate('generator') + ' ' + formats.int(shield.generator)}{units.MJ}</div>);
-      if (shield.boosters > 0) shieldTooltipDetails.push(<div key='boosters'>{translate('boosters') + ' ' + formats.int(shield.boosters)}{units.MJ}</div>);
-      if (shield.cells > 0) shieldTooltipDetails.push(<div key='cells'>{translate('cells') + ' ' + formats.int(shield.cells)}{units.MJ}</div>);
+      if (shield.generator > 0) {
+        shieldSourcesTt.push(<div key='generator'>{translate('generator') + ' ' + formats.int(shield.generator)}{units.MJ}</div>);
+        effectiveShieldAbsoluteTt.push(<div key='generator'>{translate('generator') + ' ' + formats.int(shield.generator)}{units.MJ}</div>);
+        effectiveShieldExplosiveTt.push(<div key='generator'>{translate('generator') + ' ' + formats.int(shield.generator)}{units.MJ}</div>);
+        effectiveShieldKineticTt.push(<div key='generator'>{translate('generator') + ' ' + formats.int(shield.generator)}{units.MJ}</div>);
+        effectiveShieldThermalTt.push(<div key='generator'>{translate('generator') + ' ' + formats.int(shield.generator)}{units.MJ}</div>);
+        if (shield.boosters > 0) {
+          shieldSourcesTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.int(shield.boosters)}{units.MJ}</div>);
+          effectiveShieldAbsoluteTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.int(shield.boosters)}{units.MJ}</div>);
+          effectiveShieldExplosiveTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.int(shield.boosters)}{units.MJ}</div>);
+          effectiveShieldKineticTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.int(shield.boosters)}{units.MJ}</div>);
+          effectiveShieldThermalTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.int(shield.boosters)}{units.MJ}</div>);
+        }
 
-      shieldAbsoluteTooltipDetails.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.absolute.generator)}</div>);
-      shieldAbsoluteTooltipDetails.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.absolute.boosters)}</div>);
-      shieldAbsoluteTooltipDetails.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.absolute.sys)}</div>);
+        if (shield.cells > 0) {
+          shieldSourcesTt.push(<div key='cells'>{translate('cells') + ' ' + formats.int(shield.cells)}{units.MJ}</div>);
+          effectiveShieldAbsoluteTt.push(<div key='cells'>{translate('cells') + ' ' + formats.int(shield.cells)}{units.MJ}</div>);
+          effectiveShieldExplosiveTt.push(<div key='cells'>{translate('cells') + ' ' + formats.int(shield.cells)}{units.MJ}</div>);
+          effectiveShieldKineticTt.push(<div key='cells'>{translate('cells') + ' ' + formats.int(shield.cells)}{units.MJ}</div>);
+          effectiveShieldThermalTt.push(<div key='cells'>{translate('cells') + ' ' + formats.int(shield.cells)}{units.MJ}</div>);
+        }
 
-      shieldExplosiveTooltipDetails.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.explosive.generator)}</div>);
-      shieldExplosiveTooltipDetails.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.explosive.boosters)}</div>);
-      shieldExplosiveTooltipDetails.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.explosive.sys)}</div>);
+        // Add effective shield from resistances
+        const rawMj = shield.generator + shield.boosters + shield.cells;
+        const explosiveMj = rawMj / (shield.explosive.generator * shield.explosive.boosters) - rawMj;
+        if (explosiveMj != 0) effectiveShieldExplosiveTt.push(<div key='resistance'>{translate('resistance') + ' ' + formats.int(explosiveMj)}{units.MJ}</div>);
+        const kineticMj = rawMj / (shield.kinetic.generator * shield.kinetic.boosters) - rawMj;
+        if (kineticMj != 0) effectiveShieldKineticTt.push(<div key='resistance'>{translate('resistance') + ' ' + formats.int(kineticMj)}{units.MJ}</div>);
+        const thermalMj = rawMj / (shield.thermal.generator * shield.thermal.boosters) - rawMj;
+        if (thermalMj != 0) effectiveShieldThermalTt.push(<div key='resistance'>{translate('resistance') + ' ' + formats.int(thermalMj)}{units.MJ}</div>);
 
-      shieldKineticTooltipDetails.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.kinetic.generator)}</div>);
-      shieldKineticTooltipDetails.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.kinetic.boosters)}</div>);
-      shieldKineticTooltipDetails.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.kinetic.sys)}</div>);
+        // Add effective shield from power distributor SYS pips
+        if (shield.absolute.sys != 1) {
+          effectiveShieldAbsoluteTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.int(rawMj / shield.absolute.sys - rawMj)}{units.MJ}</div>);
+          effectiveShieldExplosiveTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.int(rawMj / shield.explosive.sys - rawMj)}{units.MJ}</div>);
+          effectiveShieldKineticTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.int(rawMj / shield.kinetic.sys - rawMj)}{units.MJ}</div>);
+          effectiveShieldThermalTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.int(rawMj / shield.thermal.sys - rawMj)}{units.MJ}</div>);
+        }
+      }
 
-      shieldThermalTooltipDetails.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.thermal.generator)}</div>);
-      shieldThermalTooltipDetails.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.thermal.boosters)}</div>);
-      shieldThermalTooltipDetails.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.thermal.sys)}</div>);
+      shieldDamageTakenAbsoluteTt.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.absolute.generator)}</div>);
+      shieldDamageTakenAbsoluteTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.absolute.boosters)}</div>);
+      shieldDamageTakenAbsoluteTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.absolute.sys)}</div>);
+
+      shieldDamageTakenExplosiveTt.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.explosive.generator)}</div>);
+      shieldDamageTakenExplosiveTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.explosive.boosters)}</div>);
+      shieldDamageTakenExplosiveTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.explosive.sys)}</div>);
+
+      shieldDamageTakenKineticTt.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.kinetic.generator)}</div>);
+      shieldDamageTakenKineticTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.kinetic.boosters)}</div>);
+      shieldDamageTakenKineticTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.kinetic.sys)}</div>);
+
+      shieldDamageTakenThermalTt.push(<div key='generator'>{translate('generator') + ' ' + formats.pct1(shield.thermal.generator)}</div>);
+      shieldDamageTakenThermalTt.push(<div key='boosters'>{translate('boosters') + ' ' + formats.pct1(shield.thermal.boosters)}</div>);
+      shieldDamageTakenThermalTt.push(<div key='power distributor'>{translate('power distributor') + ' ' + formats.pct1(shield.thermal.sys)}</div>);
 
       const effectiveAbsoluteShield = shield.total / shield.absolute.total;
-      effectiveShieldData.push({ value: Math.round(effectiveAbsoluteShield), label: translate('absolute') });
+      effectiveShieldData.push({ value: Math.round(effectiveAbsoluteShield), label: translate('absolute'), tooltip: effectiveShieldAbsoluteTt });
       const effectiveExplosiveShield = shield.total / shield.explosive.total;
-      effectiveShieldData.push({ value: Math.round(effectiveExplosiveShield), label: translate('explosive') });
+      effectiveShieldData.push({ value: Math.round(effectiveExplosiveShield), label: translate('explosive'), tooltip: effectiveShieldExplosiveTt });
       const effectiveKineticShield = shield.total / shield.kinetic.total;
-      effectiveShieldData.push({ value: Math.round(effectiveKineticShield), label: translate('kinetic') });
+      effectiveShieldData.push({ value: Math.round(effectiveKineticShield), label: translate('kinetic'), tooltip: effectiveShieldKineticTt });
       const effectiveThermalShield = shield.total / shield.thermal.total;
-      effectiveShieldData.push({ value: Math.round(effectiveThermalShield), label: translate('thermal') });
+      effectiveShieldData.push({ value: Math.round(effectiveThermalShield), label: translate('thermal'), tooltip: effectiveShieldThermalTt });
 
-      shieldDamageTakenData.push({ value: Math.round(shield.absolute.total * 100), label: translate('absolute'), tooltip: shieldAbsoluteTooltipDetails });
-      shieldDamageTakenData.push({ value: Math.round(shield.explosive.total * 100), label: translate('explosive'), tooltip: shieldExplosiveTooltipDetails });
-      shieldDamageTakenData.push({ value: Math.round(shield.kinetic.total * 100), label: translate('kinetic'), tooltip: shieldKineticTooltipDetails });
-      shieldDamageTakenData.push({ value: Math.round(shield.thermal.total * 100), label: translate('thermal'), tooltip: shieldThermalTooltipDetails });
+      shieldDamageTakenData.push({ value: Math.round(shield.absolute.total * 100), label: translate('absolute'), tooltip: shieldDamageTakenAbsoluteTt });
+      shieldDamageTakenData.push({ value: Math.round(shield.explosive.total * 100), label: translate('explosive'), tooltip: shieldDamageTakenExplosiveTt });
+      shieldDamageTakenData.push({ value: Math.round(shield.kinetic.total * 100), label: translate('kinetic'), tooltip: shieldDamageTakenKineticTt });
+      shieldDamageTakenData.push({ value: Math.round(shield.thermal.total * 100), label: translate('thermal'), tooltip: shieldDamageTakenThermalTt });
 
       maxEffectiveShield = Math.max(shield.total / shield.absolute.max, shield.total / shield.explosive.max, shield.total / shield.kinetic.max, shield.total / shield.thermal.max);
     }
@@ -113,41 +153,62 @@ export default class Defence extends TranslatedComponent {
     armourSourcesData.push({ value: Math.round(armour.bulkheads), label: translate('bulkheads') });
     armourSourcesData.push({ value: Math.round(armour.reinforcement), label: translate('reinforcement') });
 
-    const armourTooltipDetails = [];
-    if (armour.bulkheads > 0) armourTooltipDetails.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.int(armour.bulkheads)}</div>);
-    if (armour.reinforcement > 0) armourTooltipDetails.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.int(armour.reinforcement)}</div>);
+    const armourSourcesTt = [];
+    const effectiveArmourAbsoluteTt = [];
+    const effectiveArmourExplosiveTt = [];
+    const effectiveArmourKineticTt = [];
+    const effectiveArmourThermalTt = [];
+    if (armour.bulkheads > 0) {
+      armourSourcesTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.int(armour.bulkheads)}</div>);
+      effectiveArmourAbsoluteTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.int(armour.bulkheads)}</div>);
+      effectiveArmourExplosiveTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.int(armour.bulkheads)}</div>);
+      effectiveArmourKineticTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.int(armour.bulkheads)}</div>);
+      effectiveArmourThermalTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.int(armour.bulkheads)}</div>);
+      if (armour.reinforcement > 0) {
+        armourSourcesTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.int(armour.reinforcement)}</div>);
+        effectiveArmourAbsoluteTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.int(armour.reinforcement)}</div>);
+        effectiveArmourExplosiveTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.int(armour.reinforcement)}</div>);
+        effectiveArmourKineticTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.int(armour.reinforcement)}</div>);
+        effectiveArmourThermalTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.int(armour.reinforcement)}</div>);
+      }
+    }
 
-    const armourAbsoluteTooltipDetails = [];
-    armourAbsoluteTooltipDetails.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.absolute.bulkheads)}</div>);
-    armourAbsoluteTooltipDetails.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.absolute.reinforcement)}</div>);
+    const rawArmour = armour.bulkheads + armour.reinforcement;
 
-    const armourExplosiveTooltipDetails = [];
-    armourExplosiveTooltipDetails.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.explosive.bulkheads)}</div>);
-    armourExplosiveTooltipDetails.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.explosive.reinforcement)}</div>);
+    const armourDamageTakenTt = [];
+    armourDamageTakenTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.absolute.bulkheads)}</div>);
+    armourDamageTakenTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.absolute.reinforcement)}</div>);
 
-    const armourKineticTooltipDetails = [];
-    armourKineticTooltipDetails.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.kinetic.bulkheads)}</div>);
-    armourKineticTooltipDetails.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.kinetic.reinforcement)}</div>);
+    const armourDamageTakenExplosiveTt = [];
+    armourDamageTakenExplosiveTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.explosive.bulkheads)}</div>);
+    armourDamageTakenExplosiveTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.explosive.reinforcement)}</div>);
+    if (armour.explosive.bulkheads * armour.explosive.reinforcement != 1) effectiveArmourExplosiveTt.push(<div key='resistance'>{translate('resistance') + ' ' + formats.int(rawArmour / (armour.explosive.bulkheads * armour.explosive.reinforcement) - rawArmour)}</div>);
 
-    const armourThermalTooltipDetails = [];
-    armourThermalTooltipDetails.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.thermal.bulkheads)}</div>);
-    armourThermalTooltipDetails.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.thermal.reinforcement)}</div>);
+    const armourDamageTakenKineticTt = [];
+    armourDamageTakenKineticTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.kinetic.bulkheads)}</div>);
+    armourDamageTakenKineticTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.kinetic.reinforcement)}</div>);
+    if (armour.kinetic.bulkheads * armour.kinetic.reinforcement != 1) effectiveArmourKineticTt.push(<div key='resistance'>{translate('resistance') + ' ' + formats.int(rawArmour / (armour.kinetic.bulkheads * armour.kinetic.reinforcement) - rawArmour)}</div>);
+
+    const armourDamageTakenThermalTt = [];
+    armourDamageTakenThermalTt.push(<div key='bulkheads'>{translate('bulkheads') + ' ' + formats.pct1(armour.thermal.bulkheads)}</div>);
+    armourDamageTakenThermalTt.push(<div key='reinforcement'>{translate('reinforcement') + ' ' + formats.pct1(armour.thermal.reinforcement)}</div>);
+    if (armour.thermal.bulkheads * armour.thermal.reinforcement != 1) effectiveArmourThermalTt.push(<div key='resistance'>{translate('resistance') + ' ' + formats.int(rawArmour / (armour.thermal.bulkheads * armour.thermal.reinforcement) - rawArmour)}</div>);
 
     const effectiveArmourData = [];
     const effectiveAbsoluteArmour = armour.total / armour.absolute.total;
-    effectiveArmourData.push({ value: Math.round(effectiveAbsoluteArmour), label: translate('absolute') });
+    effectiveArmourData.push({ value: Math.round(effectiveAbsoluteArmour), label: translate('absolute'), tooltip: effectiveArmourAbsoluteTt });
     const effectiveExplosiveArmour = armour.total / armour.explosive.total;
-    effectiveArmourData.push({ value: Math.round(effectiveExplosiveArmour), label: translate('explosive') });
+    effectiveArmourData.push({ value: Math.round(effectiveExplosiveArmour), label: translate('explosive'), tooltip: effectiveArmourExplosiveTt });
     const effectiveKineticArmour = armour.total / armour.kinetic.total;
-    effectiveArmourData.push({ value: Math.round(effectiveKineticArmour), label: translate('kinetic') });
+    effectiveArmourData.push({ value: Math.round(effectiveKineticArmour), label: translate('kinetic'), tooltip: effectiveArmourKineticTt });
     const effectiveThermalArmour = armour.total / armour.thermal.total;
-    effectiveArmourData.push({ value: Math.round(effectiveThermalArmour), label: translate('thermal') });
+    effectiveArmourData.push({ value: Math.round(effectiveThermalArmour), label: translate('thermal'), tooltip: effectiveArmourThermalTt });
 
     const armourDamageTakenData = [];
-    armourDamageTakenData.push({ value: Math.round(armour.absolute.total * 100), label: translate('absolute'), tooltip: armourAbsoluteTooltipDetails });
-    armourDamageTakenData.push({ value: Math.round(armour.explosive.total * 100), label: translate('explosive'), tooltip: armourExplosiveTooltipDetails });
-    armourDamageTakenData.push({ value: Math.round(armour.kinetic.total * 100), label: translate('kinetic'), tooltip: armourKineticTooltipDetails });
-    armourDamageTakenData.push({ value: Math.round(armour.thermal.total * 100), label: translate('thermal'), tooltip: armourThermalTooltipDetails });
+    armourDamageTakenData.push({ value: Math.round(armour.absolute.total * 100), label: translate('absolute'), tooltip: armourDamageTakenTt });
+    armourDamageTakenData.push({ value: Math.round(armour.explosive.total * 100), label: translate('explosive'), tooltip: armourDamageTakenExplosiveTt });
+    armourDamageTakenData.push({ value: Math.round(armour.kinetic.total * 100), label: translate('kinetic'), tooltip: armourDamageTakenKineticTt });
+    armourDamageTakenData.push({ value: Math.round(armour.thermal.total * 100), label: translate('thermal'), tooltip: armourDamageTakenThermalTt });
 
     return (
       <span id='defence'>
@@ -155,7 +216,7 @@ export default class Defence extends TranslatedComponent {
         <div className='group quarter'>
           <h2>{translate('shield metrics')}</h2>
           <br/>
-          <h2 onMouseOver={termtip.bind(null, <div>{shieldTooltipDetails}</div>)} onMouseOut={tooltip.bind(null, null)} className='summary'>{translate('raw shield strength')}<br/>{formats.int(shield.total)}{units.MJ}</h2>
+          <h2 onMouseOver={termtip.bind(null, <div>{shieldSourcesTt}</div>)} onMouseOut={tooltip.bind(null, null)} className='summary'>{translate('raw shield strength')}<br/>{formats.int(shield.total)}{units.MJ}</h2>
           <h2 onMouseOver={termtip.bind(null, translate('TT_TIME_TO_LOSE_SHIELDS'))} onMouseOut={tooltip.bind(null, null)}>{translate('PHRASE_TIME_TO_LOSE_SHIELDS')}<br/>{shielddamage.totalsdps == 0 ? translate('ever') : formats.time(Calc.timeToDeplete(shield.total, shielddamage.totalsdps, shielddamage.totalseps, pd.getWeaponsCapacity(), pd.getWeaponsRechargeRate() * opponentWep / 4))}</h2>
           <h2 onMouseOver={termtip.bind(null, translate('PHRASE_SG_RECOVER'))} onMouseOut={tooltip.bind(null, null)}>{translate('PHRASE_TIME_TO_RECOVER_SHIELDS')}<br/>{shield.recover === Math.Inf ? translate('never') : formats.time(shield.recover)}</h2>
           <h2 onMouseOver={termtip.bind(null, translate('PHRASE_SG_RECHARGE'))} onMouseOut={tooltip.bind(null, null)}>{translate('PHRASE_TIME_TO_RECHARGE_SHIELDS')}<br/>{shield.recharge === Math.Inf ? translate('never') : formats.time(shield.recharge)}</h2>
@@ -176,7 +237,7 @@ export default class Defence extends TranslatedComponent {
 
         <div className='group quarter'>
           <h2>{translate('armour metrics')}</h2>
-          <h2 onMouseOver={termtip.bind(null, <div>{armourTooltipDetails}</div>)} onMouseOut={tooltip.bind(null, null)} className='summary'>{translate('raw armour strength')}<br/>{formats.int(armour.total)}</h2>
+          <h2 onMouseOver={termtip.bind(null, <div>{armourSourcesTt}</div>)} onMouseOut={tooltip.bind(null, null)} className='summary'>{translate('raw armour strength')}<br/>{formats.int(armour.total)}</h2>
           <h2 onMouseOver={termtip.bind(null, translate('TT_TIME_TO_LOSE_ARMOUR'))} onMouseOut={tooltip.bind(null, null)}>{translate('PHRASE_TIME_TO_LOSE_ARMOUR')}<br/>{armourdamage.totalsdps == 0 ? translate('ever') : formats.time(Calc.timeToDeplete(armour.total, armourdamage.totalsdps, armourdamage.totalseps, pd.getWeaponsCapacity(), pd.getWeaponsRechargeRate() * opponentWep / 4))}</h2>
           <h2 onMouseOver={termtip.bind(null, translate('TT_MODULE_ARMOUR'))} onMouseOut={tooltip.bind(null, null)}>{translate('raw module armour')}<br/>{formats.int(armour.modulearmour)}</h2>
           <h2 onMouseOver={termtip.bind(null, translate('TT_MODULE_PROTECTION_EXTERNAL'))} onMouseOut={tooltip.bind(null, null)}>{translate('PHRASE_MODULE_PROTECTION_EXTERNAL')}<br/>{formats.pct1(armour.moduleprotection / 2)}</h2>
diff --git a/src/app/components/HardpointSlot.jsx b/src/app/components/HardpointSlot.jsx
index 6ac44e65..b10d22df 100644
--- a/src/app/components/HardpointSlot.jsx
+++ b/src/app/components/HardpointSlot.jsx
@@ -86,6 +86,7 @@ export default class HardpointSlot extends Slot {
           { m.getFalloff() ? <div className={'l'}>{translate('falloff')} {formats.round(m.getFalloff() / 1000)}{u.km}</div> : null }
           { m.getShieldBoost() ? <div className={'l'}>+{formats.pct1(m.getShieldBoost())}</div> : null }
           { m.getAmmo() ? <div className={'l'}>{translate('ammunition')}: {formats.int(m.getClip())}/{formats.int(m.getAmmo())}</div> : null }
+          { m.getReload() ? <div className={'l'}>{translate('reload')}: {formats.round(m.getReload())}{u.s}</div> : null }
           { m.getShotSpeed() ? <div className={'l'}>{translate('shotspeed')}: {formats.int(m.getShotSpeed())}{u.mps}</div> : null }
           { m.getPiercing() ? <div className={'l'}>{translate('piercing')}: {formats.int(m.getPiercing())}</div> : null }
           { m.getJitter() ? <div className={'l'}>{translate('jitter')}: {formats.f2(m.getJitter())}°</div> : null }
diff --git a/src/app/components/Modification.jsx b/src/app/components/Modification.jsx
index 4212e3e0..4869a694 100644
--- a/src/app/components/Modification.jsx
+++ b/src/app/components/Modification.jsx
@@ -54,6 +54,9 @@ export default class Modification extends TranslatedComponent {
     this.setState({ value });
   }
 
+  /**
+   * Triggered when an update to slider value is finished i.e. when losing focus
+   */
   _updateFinished() {
     this.props.onChange();
   }
diff --git a/src/app/components/Offence.jsx b/src/app/components/Offence.jsx
index f67f721f..18bb24b0 100644
--- a/src/app/components/Offence.jsx
+++ b/src/app/components/Offence.jsx
@@ -230,8 +230,8 @@ export default class Offence extends TranslatedComponent {
           <thead>
           <tr className='main'>
             <th rowSpan='2' className='sortable' onClick={sortOrder.bind(this, 'n')}>{translate('weapon')}</th>
-            <th colSpan='2'>{translate('opponent\`s shields')}</th>
-            <th colSpan='2'>{translate('opponent\`s armour')}</th>
+            <th colSpan='2'>{translate('opponent\'s shields')}</th>
+            <th colSpan='2'>{translate('opponent\'s armour')}</th>
           </tr>
           <tr>
             <th className='lft sortable' onMouseOver={termtip.bind(null, 'TT_EFFECTIVE_SDPS_SHIELDS')} onMouseOut={tooltip.bind(null, null)} onClick={sortOrder.bind(this, 'esdpss')}>{'sdps'}</th>
diff --git a/src/app/components/OutfittingSubpages.jsx b/src/app/components/OutfittingSubpages.jsx
index 2d25037c..e849ecfe 100644
--- a/src/app/components/OutfittingSubpages.jsx
+++ b/src/app/components/OutfittingSubpages.jsx
@@ -85,12 +85,12 @@ export default class OutfittingSubpages extends TranslatedComponent {
   _profilesTab() {
     const { ship, opponent, cargo, fuel, eng, boost, engagementRange, opponentSys } = this.props;
     const { translate } = this.context.language;
-    let realBoost = boost && ship.canBoost();
+    let realBoost = boost && ship.canBoost(cargo, fuel);
     Persist.setOutfittingTab('profiles');
 
     const engineProfileMarker = `${ship.toString()}:${cargo}:${fuel}:${eng}:${realBoost}`;
     const fsdProfileMarker = `${ship.toString()}:${cargo}:${fuel}`;
-    const movementMarker = `${ship.topSpeed}:${ship.pitch}:${ship.roll}:${ship.yaw}:${ship.canBoost()}`;
+    const movementMarker = `${ship.topSpeed}:${ship.pitch}:${ship.roll}:${ship.yaw}:${ship.canBoost(cargo, fuel)}`;
     const damageMarker = `${ship.toString()}:${opponent.toString()}:${engagementRange}:${opponentSys}`;
 
     return <div>
diff --git a/src/app/components/ShipSummaryTable.jsx b/src/app/components/ShipSummaryTable.jsx
index 9212bb1b..881a3b25 100644
--- a/src/app/components/ShipSummaryTable.jsx
+++ b/src/app/components/ShipSummaryTable.jsx
@@ -11,6 +11,8 @@ export default class ShipSummaryTable extends TranslatedComponent {
 
   static propTypes = {
     ship: React.PropTypes.object.isRequired,
+    cargo: React.PropTypes.number.isRequired,
+    fuel: React.PropTypes.number.isRequired,
     marker: React.PropTypes.string.isRequired,
   };
 
@@ -19,7 +21,7 @@ export default class ShipSummaryTable extends TranslatedComponent {
    * @return {React.Component} Summary table
    */
   render() {
-    const { ship } = this.props;
+    const { ship, cargo, fuel } = this.props;
     let { language, tooltip, termtip } = this.context;
     let translate = language.translate;
     let u = language.units;
@@ -31,9 +33,9 @@ export default class ShipSummaryTable extends TranslatedComponent {
     const sgClassNames = cn({ warning: shieldGenerator && !ship.shield, muted: !shieldGenerator });
     const sgTooltip = shieldGenerator ? 'TT_SUMMARY_SHIELDS' : 'TT_SUMMARY_SHIELDS_NONFUNCTIONAL';
     const timeToDrain = Calc.timeToDrainWep(ship, 4);
-    const canThrust = ship.canThrust();
+    const canThrust = ship.canThrust(cargo, fuel);
     const speedTooltip = canThrust ? 'TT_SUMMARY_SPEED' : 'TT_SUMMARY_SPEED_NONFUNCTIONAL';
-    const canBoost = ship.canBoost();
+    const canBoost = ship.canBoost(cargo, fuel);
     const boostTooltip = canBoost ? 'TT_SUMMARY_BOOST' : canThrust ? 'TT_SUMMARY_BOOST_NONFUNCTIONAL' : 'TT_SUMMARY_SPEED_NONFUNCTIONAL';
 
     return <div id='summary'>
diff --git a/src/app/components/StandardSlot.jsx b/src/app/components/StandardSlot.jsx
index 2d1fda65..10d4a69c 100644
--- a/src/app/components/StandardSlot.jsx
+++ b/src/app/components/StandardSlot.jsx
@@ -5,6 +5,7 @@ import TranslatedComponent from './TranslatedComponent';
 import { diffDetails } from '../utils/SlotFunctions';
 import AvailableModulesMenu from './AvailableModulesMenu';
 import ModificationsMenu from './ModificationsMenu';
+import * as ModuleUtils from '../shipyard/ModuleUtils';
 import { ListModifications, Modified } from './SvgIcons';
 import { Modifications } from 'coriolis-data/dist';
 import { stopCtxPropagation } from '../utils/UtilityFunctions';
@@ -82,7 +83,7 @@ export default class StandardSlot extends TranslatedComponent {
         menu = <AvailableModulesMenu
           className='standard'
           modules={modules}
-          shipMass={ship.ladenMass}
+          shipMass={ModuleUtils.isShieldGenerator(m.grp) ? ship.hullMass : ship.unladenMass}
           m={m}
           onSelect={onSelect}
           warning={warning}
diff --git a/src/app/components/StandardSlotSection.jsx b/src/app/components/StandardSlotSection.jsx
index 59ed2234..f57edd90 100644
--- a/src/app/components/StandardSlotSection.jsx
+++ b/src/app/components/StandardSlotSection.jsx
@@ -95,7 +95,7 @@ export default class StandardSlotSection extends SlotSection {
    * @return {Array} Array of Slots
    */
   _getSlots() {
-    let { ship, currentMenu } = this.props;
+    let { ship, currentMenu, cargo, fuel } = this.props;
     let slots = new Array(8);
     let open = this._openMenu;
     let select = this._selectModule;
@@ -135,7 +135,7 @@ export default class StandardSlotSection extends SlotSection {
       selected={currentMenu == st[1]}
       onChange={this.props.onChange}
       ship={ship}
-      warning={m => m instanceof Module ? m.getMaxMass() < (ship.ladenMass - st[1].mass + m.mass) : m.maxmass < (ship.ladenMass - st[1].mass + m.mass)}
+      warning={m => m instanceof Module ? m.getMaxMass() < (ship.unladenMass + cargo + fuel - st[1].m.mass + m.mass) : m.maxmass < (ship.unladenMass + cargo + fuel - st[1].m.mass + m.mass)}
     />;
 
 
diff --git a/src/app/pages/OutfittingPage.jsx b/src/app/pages/OutfittingPage.jsx
index cc3aec70..358443f3 100644
--- a/src/app/pages/OutfittingPage.jsx
+++ b/src/app/pages/OutfittingPage.jsx
@@ -267,15 +267,29 @@ export default class OutfittingPage extends Page {
    */
   _opponentUpdated(opponent, opponentBuild) {
     const opponentShip  = new Ship(opponent, Ships[opponent].properties, Ships[opponent].slots);
+    let opponentSys = this.state.opponentSys;
+    let opponentEng = this.state.opponentEng;
+    let opponentWep = this.state.opponentWep;
     if (opponentBuild && Persist.getBuild(opponent, opponentBuild)) {
       // Ship is a particular build
       opponentShip.buildFrom(Persist.getBuild(opponent, opponentBuild));
+      // Set pips for opponent
+      const opponentParts = Persist.getBuild(opponent, opponentBuild).split('.');
+      if (opponentParts.length >= 5) {
+        const opponentControl = LZString.decompressFromBase64(Utils.fromUrlSafe(opponentParts[4])).split('/');
+        opponentSys = parseFloat(opponentControl[0]);
+        opponentEng = parseFloat(opponentControl[1]);
+        opponentWep = parseFloat(opponentControl[2]);
+      }
     } else {
       // Ship is a stock build
       opponentShip.buildWith(Ships[opponent].defaults);
+      opponentSys = 2;
+      opponentEng = 2;
+      opponentWep = 2;
     }
 
-    this.setState({ opponent: opponentShip, opponentBuild }, () =>  this._updateRouteOnControlChange());
+    this.setState({ opponent: opponentShip, opponentBuild, opponentSys, opponentEng, opponentWep }, () =>  this._updateRouteOnControlChange());
   }
 
   /**
@@ -531,11 +545,11 @@ export default class OutfittingPage extends Page {
     const _pStr = `${ship.getPowerEnabledString()}${ship.getPowerPrioritiesString()}`;
     const _mStr = ship.getModificationsString();
 
-    const standardSlotMarker = `${ship.name}${_sStr}${_pStr}${_mStr}`;
+    const standardSlotMarker = `${ship.name}${_sStr}${_pStr}${_mStr}${ship.ladenMass}${cargo}${fuel}`;
     const internalSlotMarker = `${ship.name}${_iStr}${_pStr}${_mStr}`;
     const hardpointsSlotMarker = `${ship.name}${_hStr}${_pStr}${_mStr}`;
-    const boostMarker = `${ship.canBoost()}`;
-    const shipSummaryMarker = `${ship.name}${_sStr}${_iStr}${_hStr}${_pStr}${_mStr}`;
+    const boostMarker = `${ship.canBoost(cargo, fuel)}`;
+    const shipSummaryMarker = `${ship.name}${_sStr}${_iStr}${_hStr}${_pStr}${_mStr}${ship.ladenMass}${ship.cargo}${ship.fuel}`;
 
     return (
       <div id='outfit' className={'page'} style={{ fontSize: (sizeRatio * 0.9) + 'em' }}>
@@ -571,8 +585,8 @@ export default class OutfittingPage extends Page {
         </div>
 
         {/* Main tables */}
-        <ShipSummaryTable ship={ship} marker={shipSummaryMarker} />
-        <StandardSlotSection ship={ship} code={standardSlotMarker} onChange={shipUpdated} currentMenu={menu} />
+        <ShipSummaryTable ship={ship} fuel={fuel} cargo={cargo} marker={shipSummaryMarker} />
+        <StandardSlotSection ship={ship} fuel={fuel} cargo={cargo} code={standardSlotMarker} onChange={shipUpdated} currentMenu={menu} />
         <InternalSlotSection ship={ship} code={internalSlotMarker} onChange={shipUpdated} currentMenu={menu} />
         <HardpointSlotSection ship={ship} code={hardpointsSlotMarker} onChange={shipUpdated} currentMenu={menu} />
         <UtilitySlotSection ship={ship} code={hardpointsSlotMarker} onChange={shipUpdated} currentMenu={menu} />
diff --git a/src/app/shipyard/Calculations.js b/src/app/shipyard/Calculations.js
index ad040e0c..42dc5cee 100644
--- a/src/app/shipyard/Calculations.js
+++ b/src/app/shipyard/Calculations.js
@@ -342,7 +342,7 @@ export function shieldMetrics(ship, sys) {
 
     // Calculate diminishing returns for boosters
     // Diminishing returns not currently in-game
-    //boost = Math.min(boost, (1 - Math.pow(Math.E, -0.7 * boost)) * 2.5);
+    // boost = Math.min(boost, (1 - Math.pow(Math.E, -0.7 * boost)) * 2.5);
 
     // Remove base shield generator strength
     boost -= 1;
diff --git a/src/app/shipyard/Module.js b/src/app/shipyard/Module.js
index 37984d85..db4cb8a1 100755
--- a/src/app/shipyard/Module.js
+++ b/src/app/shipyard/Module.js
@@ -162,14 +162,6 @@ export default class Module {
     return result;
   }
 
-  /**
-   * Return true if this is a shield generator
-   * @return {Boolean} if this is a shield generator
-   */
-  isShieldGenerator() {
-    return (this.grp === 'sg' || this.grp === 'psg' || this.grp === 'bsg');
-  }
-
   /**
    * Get the power generation of this module, taking in to account modifications
    * @return {Number} the power generation of this module
diff --git a/src/app/shipyard/Ship.js b/src/app/shipyard/Ship.js
index d622254e..0de8b2ef 100755
--- a/src/app/shipyard/Ship.js
+++ b/src/app/shipyard/Ship.js
@@ -123,19 +123,23 @@ export default class Ship {
 
   /**
    * Can the ship thrust/move
+   * @param  {Number} cargo     Amount of cargo in the ship
+   * @param  {Number} fuel      Amount of fuel in the ship
    * @return {[type]} True if thrusters operational
    */
-  canThrust() {
+  canThrust(cargo, fuel) {
     return this.getSlotStatus(this.standard[1]) == 3 &&   // Thrusters are powered
-        this.ladenMass < this.standard[1].m.getMaxMass(); // Max mass not exceeded
+        this.unladenMass + cargo + fuel < this.standard[1].m.getMaxMass(); // Max mass not exceeded
   }
 
   /**
    * Can the ship boost
+   * @param  {Number} cargo     Amount of cargo in the ship
+   * @param  {Number} fuel      Amount of fuel in the ship
    * @return {[type]} True if boost capable
    */
-  canBoost() {
-    return this.canThrust() &&                                       // Thrusters operational
+  canBoost(cargo, fuel) {
+    return this.canThrust(cargo, fuel) &&                           // Thrusters operational
         this.standard[4].m.getEnginesCapacity() > this.boostEnergy; // PD capacitor is sufficient for boost
   }
 
@@ -1185,7 +1189,7 @@ export default class Ship {
   updateMovement() {
     this.speeds = Calc.speed(this.unladenMass + this.fuelCapacity, this.speed, this.standard[1].m, this.pipSpeed);
     this.topSpeed = this.speeds[4];
-    this.topBoost = this.canBoost() ? this.speeds[4] * this.boost / this.speed : 0;
+    this.topBoost = this.canBoost(0, 0) ? this.speeds[4] * this.boost / this.speed : 0;
 
     this.pitches = Calc.pitch(this.unladenMass + this.fuelCapacity, this.pitch, this.standard[1].m, this.pipSpeed);
     this.topPitch = this.pitches[4];
@@ -1204,53 +1208,13 @@ export default class Ship {
    * @return {this} The ship instance (for chaining operations)
    */
   recalculateShield() {
-    let shield = 0;
-    let shieldBoost = 1;
-    let shieldExplRes = null;
-    let shieldKinRes = null;
-    let shieldThermRes = null;
-    let shieldExplDRStart = null;
-    let shieldExplDREnd = null;
-    let shieldKinDRStart = null;
-    let shieldKinDREnd = null;
-    let shieldThermDRStart = null;
-    let shieldThermDREnd = null;
-
-    const sgSlot = this.findInternalByGroup('sg');
-    if (sgSlot && sgSlot.enabled) {
-      // Shield from generator
-      shield = Calc.shieldStrength(this.hullMass, this.baseShieldStrength, sgSlot.m, 1);
-      shieldExplRes = 1 - sgSlot.m.getExplosiveResistance();
-      shieldExplDRStart = shieldExplRes * 0.7;
-      shieldExplDREnd = 0;
-      shieldKinRes = 1 - sgSlot.m.getKineticResistance();
-      shieldKinDRStart = shieldKinRes * 0.7;
-      shieldKinDREnd = 0;
-      shieldThermRes = 1 - sgSlot.m.getThermalResistance();
-      shieldThermDRStart = shieldThermRes * 0.7;
-      shieldThermDREnd = 0;
-
-      // Shield from boosters
-      for (let slot of this.hardpoints) {
-        if (slot.enabled && slot.m && slot.m.grp == 'sb') {
-          shieldBoost += slot.m.getShieldBoost();
-          shieldExplRes *= (1 - slot.m.getExplosiveResistance());
-          shieldKinRes *= (1 - slot.m.getKineticResistance());
-          shieldThermRes *= (1 - slot.m.getThermalResistance());
-        }
-      }
-    }
-
-    // We apply diminishing returns to the boosted value
-    shieldBoost = Math.min(shieldBoost, (1 - Math.pow(Math.E, -0.7 * shieldBoost)) * 2.5);
-
-    shield = shield * shieldBoost;
-    
-    this.shield = shield;
-    this.shieldExplRes = shieldExplRes ? 1 - this.diminishingReturns(shieldExplRes, shieldExplDREnd, shieldExplDRStart) : null;
-    this.shieldKinRes = shieldKinRes ? 1 - this.diminishingReturns(shieldKinRes, shieldKinDREnd, shieldKinDRStart) : null;
-    this.shieldThermRes = shieldThermRes ? 1 - this.diminishingReturns(shieldThermRes, shieldThermDREnd, shieldThermDRStart) : null;
+    // Obtain shield metrics with 0 pips to sys (parts affected by SYS aren't used here)
+    const metrics = Calc.shieldMetrics(this, 0);
 
+    this.shield = metrics.generator ? metrics.generator + metrics.boosters : 0;
+    this.shieldExplRes = this.shield > 0 ? 1 - metrics.explosive.total : null;
+    this.shieldKinRes = this.shield > 0 ?  1 - metrics.kinetic.total : null;
+    this.shieldThermRes = this.shield > 0 ?  1 - metrics.thermal.total : null;
     return this;
   }
 
@@ -1679,11 +1643,11 @@ export default class Ship {
     let mass = this.hullMass;
     mass += m.pp ? m.pp.getMass() : ModuleUtils.standard(0, '2D').getMass();
     mass += m.th ? m.th.getMass() : ModuleUtils.standard(1, '2D').getMass();
-    mass += m.fsd ? m.fsd.getMass() : ModuleUtils.standard(2, this.standard[2].maxClass + 'D').getMass();
+    mass += m.fsd ? m.fsd.getMass() : ModuleUtils.standard(2, '2D').getMass();
     mass += m.ls ? m.ls.getMass() : ModuleUtils.standard(3, this.standard[3].maxClass + 'D').getMass() * 0.3; // Lightweight grade 4 mod reduces mass by up to 70%
-    mass += m.pd ? m.pd.getMass() : ModuleUtils.standard(4, '2D').getMass();
-    mass += m.s ? m.s.getMass() : ModuleUtils.standard(5, this.standard[5].maxClass + 'D').getMass();
-    mass += m.ft ? m.ft.getMass() : ModuleUtils.standard(6, '1C').getMass();
+    mass += m.pd ? m.pd.getMass() : ModuleUtils.standard(4, '1D').getMass();
+    mass += m.s ? m.s.getMass() : ModuleUtils.standard(5, this.standard[5].maxClass + 'D').getMass() * 0.2; // Lightweight grade 5 mod reduces mass by up to 80%
+    // Ignore fuel tank as it could be empty
     return mass;
   }
 
diff --git a/src/app/utils/CompanionApiUtils.js b/src/app/utils/CompanionApiUtils.js
index 5f6df7c5..25124864 100644
--- a/src/app/utils/CompanionApiUtils.js
+++ b/src/app/utils/CompanionApiUtils.js
@@ -3,6 +3,7 @@ import { Modifications, Modules, Ships } from 'coriolis-data/dist';
 import Module from '../shipyard/Module';
 import Ship from '../shipyard/Ship';
 import { getBlueprint } from '../utils/BlueprintFunctions';
+import * as ModuleUtils from '../shipyard/ModuleUtils';
 
 // mapping from fd's ship model names to coriolis'
 const SHIP_FD_NAME_TO_CORIOLIS_NAME = {
@@ -378,7 +379,7 @@ function _addModifications(module, modifiers, blueprint, grade) {
   
   // Shield generator resistance is actually a damage modifier, so needs to be inverted.
   // In addition, the modification is based off the inherent resistance of the module
-  if (module.isShieldGenerator()) {
+  if (ModuleUtils.isShieldGenerator(module.grp)) {
     if (module.getModValue('explres')) {
       module.setModValue('explres', ((1 - (1 - module.explres) * (1 + module.getModValue('explres') / 10000)) - module.explres) * 10000);
     }
diff --git a/src/app/utils/SlotFunctions.js b/src/app/utils/SlotFunctions.js
index 8a57e63e..c2f5f4ba 100644
--- a/src/app/utils/SlotFunctions.js
+++ b/src/app/utils/SlotFunctions.js
@@ -1,9 +1,9 @@
 import React from 'react';
 import cn from 'classnames';
-import { isShieldGenerator } from '../shipyard/ModuleUtils';
 import Module from '../shipyard/Module';
 import { Infinite } from '../components/SvgIcons';
 import Persist from '../stores/Persist';
+import * as ModuleUtils from '../shipyard/ModuleUtils';
 
 /**
  * Determine if a slot on a ship can mount a module of a particular class and group
@@ -159,8 +159,8 @@ export function diffDetails(language, m, mm) {
   let mmDps = mm ? mm.getDps() || 0 : 0;
   if (mDps && mDps != mmDps) propDiffs.push(<div key='dps'>{translate('dps')}: <span className={diffClass(mmDps, mDps, true)}>{diff(formats.round, mDps, mmDps)}</span></div>);
 
-  let mAffectsShield = isShieldGenerator(m.grp)  || m.grp == 'sb';
-  let mmAffectsShield = isShieldGenerator(mm ? mm.grp : null) || mm && mm.grp == 'sb';
+  let mAffectsShield = ModuleUtils.isShieldGenerator(m.grp)  || m.grp == 'sb';
+  let mmAffectsShield = mm ? ModuleUtils.isShieldGenerator(m.grp) || mm.grp == 'sb' : false;
   if (mAffectsShield || mmAffectsShield) {
     let shield = this.calcShieldStrengthWith(); // Get shield strength regardless of slot active / inactive
     let newShield = 0;