diff --git a/polymer-flex-layout/polymer-flex-panel.html b/polymer-flex-layout/polymer-flex-panel.html
index 81048e1..54260ab 100644
--- a/polymer-flex-layout/polymer-flex-panel.html
+++ b/polymer-flex-layout/polymer-flex-panel.html
@@ -3,8 +3,13 @@
 Use of this source code is governed by a BSD-style
 license that can be found in the LICENSE file.
 -->
-<polymer-element name="polymer-flex-panel" extends="polymer-flex-layout" noscript isContainer>
+<polymer-element name="polymer-flex-panel" extends="polymer-flex-layout" noscript>
   <template>
     <shadow></shadow>
   </template>
+  <script>
+    Polymer('polymer-flex-panel', {
+      isContainer: true
+    });
+  </script>
 </polymer-element>