UName Trolley Brake Swivel Caster, Casters Swivel Top Plate 3-Inch Wheel Diameter, 2 Rigid 2 with Brake, Red, 150-lb Load Capacity, Set of 4 UN242 Material: Polyurethane, Metal 3'' Diameter Rubber Wheel Top Plate: 3.6'' x 2.5'', Aperture: 0.33'', Overall Height: 4.2'' 150-Lb load capacity per caster Package Content: 2 x Brake Caster Wheel 2 x Swivel Caster Wheel