This 5" x 2" Solid Elastomer Swivel Kingpin Caster consists of pressed steel, with ball bearings. Features: Bolted wheel axle and Zinc-plated. This caster includes very high operational comfort through the especially thick, elastic tread, low-noise operation, low rolling resistance, excellent floor conservation, very high chafting resistance, high cut and tear propagation resistance, and very good chemical linkage with the wheel center.