"The Fairbanks Caster Quick-Change Pad is a one-pc., heavy-duty 10-gauge formed steel weld-on mounting pad for swivel and rigid casters. Top plate measures 4in. x 4 1/2in. Caster is securely held in place with a single 5/16in. diameter cross bolt on one end and an integral retaining clip on the other end. Corrosion-resistant zinc-plated finish. U.S.A. Product Type Mounting pad, Caster Type Swivel and rigid. Pad size 4 3/8in. x 5 9/16in. Height 1 1/8in. Caster top plate size 4in. x 4 1/2in. Cross bolt diameter 5/16in."