diff --git a/lib/interaction_box.js b/lib/interaction_box.js
index 2e8363b..7f8641a 100644
--- a/lib/interaction_box.js
+++ b/lib/interaction_box.js
@@ -1,4 +1,4 @@
-var glMatrix = require("gl-matrix")
+let glMatrix = require("gl-matrix")
   , vec3 = glMatrix.vec3;
 
 /**