 		protected var _thumbButton:Button;
 		protected var _trackSkin:DisplayObject;
 		protected var _isThumbPressed:Boolean = false;
-		protected var _thumbButtonHeight:Number=NaN;
-		protected var _thumbButtonWidth:Number = NaN;
+		protected var _thumbButtonHeight:Number= 20;
+		protected var _thumbButtonWidth:Number = 20;
 		
 		public function Slider(direction:String)
 		{

			}
		}
		

	}
}
			if(!_thumbButton)
			{
				thumbButton = new Button();
				thumbButton.width = _thumbButtonWidth;
				thumbButton.height = _thumbButtonHeight;
			}
		}
		
