diff --git a/player/js/utils/expressions/ShapeInterface.js b/player/js/utils/expressions/ShapeInterface.js
index ebd4150..d975f68 100644
--- a/player/js/utils/expressions/ShapeInterface.js
+++ b/player/js/utils/expressions/ShapeInterface.js
@@ -546,6 +546,7 @@
             },
             '_name': { value: shape.nm },
             'ix': { value: shape.ix },
+            'propertyIndex': { value: shape.ix },
             'mn': { value: shape.mn }
         });
         return interfaceFunction;