diff --git a/src/app/components/AvailableModulesMenu.jsx b/src/app/components/AvailableModulesMenu.jsx
index b3fda06f..6b8faed6 100644
--- a/src/app/components/AvailableModulesMenu.jsx
+++ b/src/app/components/AvailableModulesMenu.jsx
@@ -128,6 +128,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
     m: PropTypes.object,
     shipMass: PropTypes.number,
     warning: PropTypes.func,
+    disable: PropTypes.func,
     firstSlotId: PropTypes.string,
     lastSlotId: PropTypes.string,
     activeSlotId: PropTypes.string,
@@ -159,7 +160,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
    */
   _initState(props, context) {
     let translate = context.language.translate;
-    let { m, warning, shipMass, onSelect, modules, firstSlotId, lastSlotId } = props;
+    let { m, warning, disable, shipMass, onSelect, modules, firstSlotId, lastSlotId } = props;
     let list, currentGroup;
 
     let buildGroup = this._buildGroup.bind(
@@ -167,6 +168,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
       translate,
       m,
       warning,
+      disable,
       shipMass - (m && m.mass ? m.mass : 0),
       (m, event) => {
         this._hideDiff(event);
@@ -258,6 +260,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
    * @param  {Function} translate   Translate function
    * @param  {Object} mountedModule Mounted Module
    * @param  {Function} warningFunc Warning function
+   * @param  {Function} disableFunc Function when selection should be disabled
    * @param  {number} mass          Mass
    * @param  {function} onSelect    Select/Mount callback
    * @param  {string} grp           Group name
@@ -266,7 +269,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
    * @param  {string} lastSlotId    id of last slot item
    * @return {React.Component}      Available Module Group contents
    */
-  _buildGroup(translate, mountedModule, warningFunc, mass, onSelect, grp, modules, firstSlotId, lastSlotId) {
+  _buildGroup(translate, mountedModule, warningFunc, disableFunc, mass, onSelect, grp, modules, firstSlotId, lastSlotId) {
     let prevClass = null, prevRating = null, prevName;
     let elems = [];
 
@@ -284,6 +287,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
       let m = sortedModules[i];
       let mount = null;
       let disabled = false;
+      let softDisabled = disableFunc && disableFunc(m);
       prevName = m.name;
       if (ModuleUtils.isShieldGenerator(m.grp)) {
         // Shield generators care about maximum hull mass
@@ -294,7 +298,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
       }
       let active = mountedModule && mountedModule.id === m.id;
       let classes = cn(m.name ? 'lc' : 'c', {
-        warning: !disabled && warningFunc && warningFunc(m),
+        warning: !disabled && (softDisabled || (warningFunc && warningFunc(m))),
         active,
         disabled
       });
@@ -316,7 +320,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
         this.lastSlotId = sortedModules[i].id;
 
         let showDiff = this._showDiff.bind(this, mountedModule, m);
-        let select = onSelect.bind(null, m);
+        let select = softDisabled ? () => {} : onSelect.bind(null, m);
 
         eventHandlers = {
           onMouseEnter: this._over.bind(this, showDiff),
@@ -344,7 +348,7 @@ export default class AvailableModulesMenu extends TranslatedComponent {
         // elems.push(<br key={'b' + m.grp + i} />);
         itemsOnThisRow = 0;
       }
-      if (itemsOnThisRow == 6 || i > 0 && sortedModules.length > 3 && itemsPerClass > 2 && m.class != prevClass && (m.rating != prevRating || m.mount)) {
+      if (itemsOnThisRow == 4 || i > 0 && sortedModules.length > 3 && itemsPerClass > 2 && m.class != prevClass && (m.rating != prevRating || m.mount)) {
         elems.push(<br key={'b' + m.grp + i}/>);
         itemsOnThisRow = 0;
       }
diff --git a/src/app/components/Slot.jsx b/src/app/components/Slot.jsx
index 8bd080ec..d083449e 100644
--- a/src/app/components/Slot.jsx
+++ b/src/app/components/Slot.jsx
@@ -7,6 +7,20 @@ import ModificationsMenu from './ModificationsMenu';
 import { diffDetails } from '../utils/SlotFunctions';
 import { wrapCtxMenu } from '../utils/UtilityFunctions';
 
+/**
+ * Returns a function that checks that a given module does not exceed the limit
+ * of experimental modules.
+ * @param {Ship} ship Ship to check experimentals for
+ * @return {Function} Checker function that returns true if the number of
+ * experimentals is exceeded
+ */
+function experimentalTracker(ship) {
+  return (m) => {
+    return m.experimental &&
+      4 <= ship.hardpoints.reduce((r, o) => o.m && o.m.experimental ? r + 1 : r, 0);
+  };
+}
+
 /**
  * Abstract Slot
  */
@@ -133,6 +147,7 @@ export default class Slot extends TranslatedComponent {
           warning={warning}
           diffDetails={diffDetails.bind(ship, this.context.language)}
           slotDiv = {this.slotDiv}
+          disable={experimentalTracker(ship)}
         />;
       }
     }