Sturdy Hardware Heavy Duty Casters Wheel Diameter: 6" 150mm Wheel Width: 2" 50mm Wheel Material: Polyurethane on Steel, Rubber on Steel,Polyolefin Wheel Color: red, black,blue Overall Height: 190mm Bearing: Doubld Ball Bearing,roller bearing Capacity: 300-500KG Top Plate: 114 x 100 Plate Thickness: 6mm Finish: Zinc. Sturdy Hardware Swivel Heavy Duty Casters offer highest strength in the industry. A cost effective solution for high capacity applications like movable racks, conveyor, utility trucks, storage racks, Foot stand and so on. Packed into the crate.