diff --git a/lib/6to5/traverse/index.js b/lib/6to5/traverse/index.js
index 12620d6e16..b8ef5ce920 100644
--- a/lib/6to5/traverse/index.js
+++ b/lib/6to5/traverse/index.js
@@ -76,7 +76,7 @@ function traverse(parent, callbacks, opts) {
     };
 
     if (_.isArray(nodes)) {
-      for (var i in nodes) {
+      for (i in nodes) {
         handle(nodes, i);
       }