diff --git a/model/serializeConfig.js b/model/serializeConfig.js
index 08b12d04..0c1108b1 100755
--- a/model/serializeConfig.js
+++ b/model/serializeConfig.js
@@ -14,25 +14,28 @@ var ARRAY_LAST_ELEMENT_ID = 0;
 
 var KEY_ACTION_ID_KEYSTROKE_SCANCODE_FIRST        = 1;
 var KEY_ACTION_ID_KEYSTROKE_SCANCODE_LAST         = 231;
-var KEY_ACTION_ID_SWITCH_LAYER_MOD                = 232;
-var KEY_ACTION_ID_SWITCH_LAYER_FN                 = 233;
-var KEY_ACTION_ID_SWITCH_LAYER_MOUSE              = 234;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_MOD         = 235;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_FN          = 236;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_MOUSE       = 237;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_CTRL   = 238;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_SHIFT  = 239;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_ALT    = 240;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_SUPER  = 241;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_CTRL  = 242;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_SHIFT = 243;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_ALT   = 244;
-var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_SUPER = 245;
-var KEY_ACTION_ID_MOUSE                           = 246;
-var KEY_ACTION_ID_PLAY_MACRO                      = 247;
-var KEY_ACTION_ID_SWITCH_KEYMAP                   = 248;
+var KEY_ACTION_ID_SWITCH_LAYER                    = 232;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_MOD         = 233;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_FN          = 234;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_MOUSE       = 235;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_CTRL   = 236;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_SHIFT  = 237;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_ALT    = 238;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_LEFT_SUPER  = 239;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_CTRL  = 240;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_SHIFT = 241;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_ALT   = 242;
+var KEY_ACTION_ID_DUAL_ROLE_KEYSTROKE_RIGHT_SUPER = 243;
+var KEY_ACTION_ID_MOUSE                           = 244;
+var KEY_ACTION_ID_PLAY_MACRO                      = 245;
+var KEY_ACTION_ID_SWITCH_KEYMAP                   = 246;
 var KEY_ACTION_ID_NONE                            = 255;
 
+var SWITCH_LAYER_MOD    = 0;
+var SWITCH_LAYER_FN     = 1;
+var SWITCH_LAYER_MOUSE  = 2;
+var SWITCH_LAYER_TOGGLE = 0x80;
+
 var NONE_ACTION_PADDING = 0;
 
 var MOUSE_ACTION_ID_LEFT_CLICK   = 0;
@@ -141,12 +144,12 @@ function serializeSwitchKeymapAction(switchKeymapAction) {
 }
 
 function serializeSwitchLayerAction(switchLayerAction) {
+    writer.uint8(KEY_ACTION_ID_SWITCH_LAYER);
     writer.uint8({
-        mod  : KEY_ACTION_ID_SWITCH_LAYER_MOD,
-        fn   : KEY_ACTION_ID_SWITCH_LAYER_FN,
-        mouse: KEY_ACTION_ID_SWITCH_LAYER_MOUSE
-    }[switchLayerAction]);
-    writer.uint8(0);
+        mod  : SWITCH_LAYER_MOD,
+        fn   : SWITCH_LAYER_FN,
+        mouse: SWITCH_LAYER_MOD
+    }[switchLayerAction] | switchLayerAction.toggle ? SWITCH_LAYER_TOGGLE : 0);
 }
 
 serializeKeyActions(keyActions);
diff --git a/model/uhk-config.json b/model/uhk-config.json
index 65ad5522..211836c4 100644
--- a/model/uhk-config.json
+++ b/model/uhk-config.json
@@ -38,7 +38,8 @@
                                 },
                                 {
                                     "actionType": "switchLayer",
-                                    "layer": "fn"
+                                    "layer": "fn",
+                                    "toggle": false
                                 },
                                 {
                                     "actionType": "dualRoleKeystroke",