Stem Caster, Swivel Caster with Brake, 220 lb Load Rating, 0 to 299 lb, 4 in Wheel Dia., 2 3/4 in Wheel Width, Polyurethane Wheel/Tread Material, 120 mm Mounting Height, Ball, 5/32 in x 25/32 in Caster Stem Size, Threaded, Nylon Caster Frame Material, Unfinished Frame Finish, Yes Non-Marking, 2 Number of Wheels