12 gauge shelves handle the heaviest of loads. Available in 2 or 3 shelf models. Shelves available with flush edges, or with 1-1/2? retaining lip. 2 swivel and 2 rigid casters with 6? x 2? hard tread phenolic wheels for added maneuverability under heavy loads. Swivel casters have wheel brakes to stop unwanted movement when loading and unloading. 36? overall height.