diff --git a/ionic/collide/animation-stop.js b/ionic/collide/animation-stop.js
index 8f68a01a92..cf0861e619 100644
--- a/ionic/collide/animation-stop.js
+++ b/ionic/collide/animation-stop.js
@@ -13,8 +13,8 @@ export function animationStop(elements, options, propertiesMap) {
   *******************/
 
   /* Clear the currently-active delay on each targeted element. */
-  for (var x = 0; x < elements.length; x++) {
-    eleData = Collide.data(elements[x]);
+  for (var i = 0, l = elements.length; i < l; i++) {
+    eleData = Collide.data(elements[i]);
 
     if (eleData && eleData.delayTimer) {
       /* Stop the timer from triggering its cached next() function. */
@@ -42,10 +42,10 @@ export function animationStop(elements, options, propertiesMap) {
      regardless of the element's current queue state. */
 
   /* Iterate through every active call. */
-  for (var x = 0, callsLength = Collide.State.calls.length; x < callsLength; x++) {
+  for (var i = 0, l = Collide.State.calls.length; i < l; i++) {
 
     /* Inactive calls are set to false by the logic inside completeCall(). Skip them. */
-    activeCall = Collide.State.calls[x];
+    activeCall = Collide.State.calls[i];
     if (activeCall) {
 
       /* Iterate through the active call's targeted elements. */
@@ -107,7 +107,7 @@ export function animationStop(elements, options, propertiesMap) {
 
     }
 
-  } // END: for (var x = 0, l = Collide.State.calls.length; x < l; x++) {
+  } // END: for (var i = 0, l = Collide.State.calls.length; x < l; x++) {
 
   /* Prematurely call completeCall() on each matched active call. Pass an additional flag for 'stop' to indicate
      that the complete callback and display:none setting should be skipped since we're completing prematurely. */
diff --git a/ionic/collide/calculate-unit-ratios.js b/ionic/collide/calculate-unit-ratios.js
index fd27cbb0ad..a9277d4f0b 100644
--- a/ionic/collide/calculate-unit-ratios.js
+++ b/ionic/collide/calculate-unit-ratios.js
@@ -61,8 +61,8 @@ export function calculateUnitRatios(element, callUnitConversionData) {
        Similarly, since width/height can be artificially constrained by their min-/max- equivalents, these are controlled for as well. */
     /* Note: Overflow must be also be controlled for per-axis since the overflow property overwrites its per-axis values. */
     var cssPropNames = [ 'overflow', 'overflowX', 'overflowY' ];
-    for (var x = 0; x < overflows.length; x++) {
-      Collide.CSS.setPropertyValue(dummy, cssPropNames[x], 'hidden');
+    for (var i = 0; i < overflows.length; i++) {
+      Collide.CSS.setPropertyValue(dummy, cssPropNames[i], 'hidden');
     }
 
     Collide.CSS.setPropertyValue(dummy, 'position', sameRatioIndicators.position);
@@ -71,8 +71,8 @@ export function calculateUnitRatios(element, callUnitConversionData) {
 
     /* width and height act as our proxy properties for measuring the horizontal and vertical % ratios. */
     cssPropNames = [ 'minWidth', 'maxWidth', 'width', 'minHeight', 'maxHeight', 'height' ];
-    for (var x = 0; x < overflows.length; x++) {
-      Collide.CSS.setPropertyValue(dummy, cssPropNames[x], measurement + '%');
+    for (var i = 0; i < overflows.length; i++) {
+      Collide.CSS.setPropertyValue(dummy, cssPropNames[i], measurement + '%');
     }
 
     /* paddingLeft arbitrarily acts as our proxy property for the em ratio. */
diff --git a/ionic/collide/easing.js b/ionic/collide/easing.js
index e5a9757ae3..f1a9930665 100644
--- a/ionic/collide/easing.js
+++ b/ionic/collide/easing.js
@@ -267,8 +267,8 @@ Collide.Easings = {
     [ "easeInOutCirc", [ 0.785, 0.135, 0.15, 0.86 ] ]
   ];
 
-  for (let x = 0; x < penner.length; x++) {
-    Collide.Easings[ penner[x][0] ] = generateBezier.apply(null, penner[x][1]);
+  for (var i = 0, l = penner.length; i < l; i++) {
+    Collide.Easings[ penner[i][0] ] = generateBezier.apply(null, penner[i][1]);
   }
 
 })();