"The Fairbanks Rigid Weldless Caster features one-piece construction to eliminate stress build-up. Double ball raceways and seal ring keep lubrication in and dirt out. U.S.A. Wheel Diameter in. 6, Wheel Width in. 2, Material Type Steel, Finish Type Gray, Top Plate Dimensions L x W in. 4 1/2 x 4, Capacity lbs. 1,100, Casters qty. 1, Wheel Type Polyurethane/semi-steel core, Bolt Hole Spacing 3-3 5/8 x 2 5/8-3, Foot Brake No, Caster Type Rigid, Mount Height in. 7 1/4, Overall Height in. 7 1/4, Bearing Type Roller. 3/4in. king pin One piece fork assures less failure and longer life Durable powder-coat finish Rugged polyurethane on cast iron wheel 1,100 lb. capacity"