diff --git a/source/Ox.UI/js/List/Ox.TreeList.js b/source/Ox.UI/js/List/Ox.TreeList.js
index 3b36ad43..a9d5d72a 100644
--- a/source/Ox.UI/js/List/Ox.TreeList.js
+++ b/source/Ox.UI/js/List/Ox.TreeList.js
@@ -107,7 +107,7 @@ Ox.TreeList = function(options, self) {
                 .appendTo($item);
         }
         $('<div>')
-            .addClass('OxCell OxTarget'+!data.items?' OxSelectable':'')
+            .addClass('OxCell OxTarget'+(!data.items?' OxSelectable':''))
             .css({
                 width: (self.options.width - padding - 32 + !data.items * 16) + 'px'
             })