Extender helps add height to 19.75 x 19.75" OptiClean wash rack (sold separately) for storage and transportation of glasses, dinnerware, and other items Made of polypropylene for resistance to breakage and fatigue, chemicals, and heat Honeycomb sides with rounded edges to help distribute load and provide handholds for gripping Snap extensions on edge-bottom to facilitate snapping extender on and off wash rack Measures 19.75 x 19.75 x 1.75"