diff --git a/lib/make/units.js b/lib/make/units.js
index a4f25e5..3933c2c 100644
--- a/lib/make/units.js
+++ b/lib/make/units.js
@@ -9,7 +9,7 @@ make.unit = {
     ]);
   },
   length: function () {
-    return make.numbers.number() + make.units.units();
+    return make.numbers.number() + make.unit.units();
   },
   percent: function () {
     return make.numbers.number() + "%";