diff --git a/js/ComboBox.js b/js/ComboBox.js
index cb9ba834..c9a12d4e 100644
--- a/js/ComboBox.js
+++ b/js/ComboBox.js
@@ -46,6 +46,7 @@ define( require => {
 
     options = _.extend( {
 
+      align: 'left', // {string} alignment of items on the button and in the list, see ALIGN_VALUES
       labelNode: null, // optional label, placed to the left of the combo box
       labelXSpacing: 10, // horizontal space between label and combo box
       enabledProperty: new Property( true ),
diff --git a/js/ComboBoxButtonNode.js b/js/ComboBoxButtonNode.js
index f972da9e..440e99df 100644
--- a/js/ComboBoxButtonNode.js
+++ b/js/ComboBoxButtonNode.js
@@ -22,9 +22,9 @@ define( require => {
   // constants
   const DEFAULT_OPTIONS = {
 
+    //TODO sun#430 rename this to arrowDirection, 'up' or 'down'
     // used by ComboBox and ButtonNode
-    listPosition: 'below', // {string} where the list is positioned relative to the button, see LIST_POSITION_VALUES
-    align: 'left', // {string} alignment of items on the button and in the list, see ALIGN_VALUES
+    listPosition: 'below', // {string} where the list is positioned relative to the button
 
     // used exclusively by ButtonNode
     buttonFill: 'white',