The Bronco Waste Container Dolly is round with five swivel casters to move around heavy trash containers. The Dolly is designed to fit 20, 32, 44 and 55 gallon containers. Place the container on top of the dish and twist until it locks. The casters are non-marking 3" swivel that will cleanly roll over a variety on indoor and outdoor surfaces. BPA free. - Plastic; black - NSF listed - Diameter 17-9/10 in - Height 5 in - Sold per each