"The Fairbanks Swivel Weldless Caster features one-piece construction to eliminate stress build-up. Double ball raceways and seal ring keep lubrication in and dirt out. 2 5/8in. to 3in. x 3in. to 3 5/8in. bolt hole spacing. 3/4in. king pin. Top plate size 4in. x 4 1/2in. U.S.A. Wheel Diameter in. 4, Capacity lbs. 800, Foot Brake No, Casters qty. 1, Bearing Type Roller, Top Plate Dimensions L x W in. 4 1/2 x 4, Finish Type Gray, Caster Type Swivel, Overall Height in. 5 5/8, Bolt Hole Spacing 3-3 5/8 x 2 5/8-3, Wheel Width in. 2, Material Type Steel, Wheel Type Phenolic canvas, Mount Height in. 5 5/8. One-piece fork assures less failure and longer life 3/4in. king pin is orbital cold forged for superior strength and stability Nylon grease seal keeps dirt and debris out of the upper ball raceway Gray powder-coat finish prevents corrosion Rugged polyolefin wheel 800-lb. capacity"