This set of 4 casters has a universal plate that will fit a variety of carts and fixtures. The blue polyurethane material is grease resistant and non-marking to help keep flooring clean. This set of casters feature a friction style brake that will keep your fixture or cart in place. 300 lb capacity per caster. Plate size is 4" x 4" with 1 3/4" plate hole spacing. Zinc plated steel.