4″ Rigid Hard Rubber Top Plate 3-1/4″ x 6-1/4″ 21HR40 Top plate size and bolt hole configurations match industry specifications Mobility and durability combination
4″ Rigid Soft Rubber Top Plate 3-1/4″ x 6-1/4″ 21SR40 Top plate size and bolt hole configurations match industry specifications Mobility and durability combination
4″ Swivel Hard Rubber Top Plate 4″ x 5″ 00HR40 Top plate size and bolt hole configurations match industry specifications Mobility and durability combination
4″ Swivel Hard Rubber With Brake Top Plate 4″ x 5″ 00HR40-B Top plate size and bolt hole configurations match industry specifications Mobility and durability combination
4″ Swivel Soft Rubber Top Plate 4″ x 5″ 00SR40 Top plate size and bolt hole configurations match industry specifications Mobility and durability combination
4″ Swivel Soft Rubber With Brake Top Plate 4″ x 5″ 00SR40-B Top plate size and bolt hole configurations match industry specifications Mobility and durability combination