diff --git a/test/hand.js b/test/hand.js
index 1c3e8e6..0e178ac 100644
--- a/test/hand.js
+++ b/test/hand.js
@@ -1,8 +1,8 @@
 describe('Hand', function(){
   describe("an instance", function() {
-    var data = fakeFrame({fingers: 5, hands:1})
-    var frame = createFrame(data);
-    var hand = frame.hands[0];
+    let data = fakeFrame({fingers: 5, hands:1})
+    let frame = createFrame(data);
+    let hand = frame.hands[0];
 
     describe("properties", function() {
       it('should have palmPosition', function() { assert(hand.palmPosition) })
@@ -32,8 +32,8 @@ describe('Hand', function(){
 
 
       it('should return fingers ordered by id', function(){
-        var hand = fakeActualFrame().hands[0];
-        for (var i = 1; i < hand.fingers.length; i++){
+        let hand = fakeActualFrame().hands[0];
+        for (let i = 1; i < hand.fingers.length; i++){
           assert(hand.fingers[i].id > hand.fingers[i-1].id,
               "Fingers to be in sequential order. Got '" + hand.fingers[i].id + ', ' + hand.fingers[i-1].id + "'");
         }
@@ -42,11 +42,11 @@ describe('Hand', function(){
 
     describe("#rotationAngle", function() {
       it('should work', function() {
-        var frame1 = createFrame(data);
+        let frame1 = createFrame(data);
         frame1.hand(0)._rotation = [1.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,1.0];
-        var frame2 = createFrame(data);
+        let frame2 = createFrame(data);
         frame2.hand(0)._rotation = [1.0,0.0,0.0,0.0,1.0,0.0,0.5,0.0,0.5];
-        var result = frame2.hand(0).rotationAngle(frame1);
+        let result = frame2.hand(0).rotationAngle(frame1);
         assert.closeTo(0.72273, result, 0.0001)
       })
     })
@@ -54,30 +54,30 @@ describe('Hand', function(){
 
   describe('#translation()', function(){
     it('should return the translation', function(){
-      var data1 = fakeFrame({handData: [fakeHand({translation: [1, 2, 3]})]})
-      var frame1 = createFrame(data1);
-      var data2 = fakeFrame({handData: [fakeHand({translation: [3, 1, 5]})]})
-      var frame2 = createFrame(data2);
+      let data1 = fakeFrame({handData: [fakeHand({translation: [1, 2, 3]})]})
+      let frame1 = createFrame(data1);
+      let data2 = fakeFrame({handData: [fakeHand({translation: [3, 1, 5]})]})
+      let frame2 = createFrame(data2);
       assert.deepEqual([-2, 1, -2], frame1.hand(0).translation(frame2))
     })
   })
 
   describe('#rotationAxis()', function(){
     it('should return the rotationAxis', function(){
-      var data1 = fakeFrame({handData: [fakeHand({rotation: [[0,1,2], [2,3,4], [2,3,4]]})]})
-      var frame1 = createFrame(data1);
-      var data2 = fakeFrame({handData: [fakeHand({rotation: [[0,4,5], [1,3,7], [5,4,2]]})]})
-      var frame2 = createFrame(data2);
-      var result = frame1.hand(0).rotationAxis(frame2);
+      let data1 = fakeFrame({handData: [fakeHand({rotation: [[0,1,2], [2,3,4], [2,3,4]]})]})
+      let frame1 = createFrame(data1);
+      let data2 = fakeFrame({handData: [fakeHand({rotation: [[0,4,5], [1,3,7], [5,4,2]]})]})
+      let frame2 = createFrame(data2);
+      let result = frame1.hand(0).rotationAxis(frame2);
       assertUtil.vectorCloseTo([-0.74278, -0.55708,-0.37139], result, 0.0001, 'rotation axis');
     })
 
     it('should return a null vector if the hand is invalid', function(){
-      var data1 = fakeFrame({handData: [fakeHand({rotation: [[0,4,5], [1,3,7], [5,4,2]]})]})
-      var frame1 = createFrame(data1);
-      var data2 = fakeFrame({handData: []})
-      var frame2 = createFrame(data2);
-      var result = frame1.hand(0).rotationAxis(frame2);
+      let data1 = fakeFrame({handData: [fakeHand({rotation: [[0,4,5], [1,3,7], [5,4,2]]})]})
+      let frame1 = createFrame(data1);
+      let data2 = fakeFrame({handData: []})
+      let frame2 = createFrame(data2);
+      let result = frame1.hand(0).rotationAxis(frame2);
       assert(!frame2.hand(0).valid);
       assertUtil.vectorCloseTo(result, Leap.vec3.create(), 0.0001, 'result is zero vector');
     });
@@ -85,11 +85,11 @@ describe('Hand', function(){
 
   describe('#rotationAngle()', function(){
     it('should return the rotationAngle', function(){
-      var data1 = fakeFrame({handData: [fakeHand({rotation: [[1,0,0], [0,1,0], [0,0,1]]})]})
-      var frame1 = createFrame(data1);
-      var data2 = fakeFrame({handData: [fakeHand({rotation: [[1,0,0], [0,1,0], [0.5,0,0.5]]})]})
-      var frame2 = createFrame(data2);
-      var result = frame1.hand(0).rotationAngle(frame2);
+      let data1 = fakeFrame({handData: [fakeHand({rotation: [[1,0,0], [0,1,0], [0,0,1]]})]})
+      let frame1 = createFrame(data1);
+      let data2 = fakeFrame({handData: [fakeHand({rotation: [[1,0,0], [0,1,0], [0.5,0,0.5]]})]})
+      let frame2 = createFrame(data2);
+      let result = frame1.hand(0).rotationAngle(frame2);
       assert.closeTo(0.72273, result, 0.0001)
     })
   })