Listing is for a set of four (4) Service Caster Series #KP30 casters, two (2) swivel casters with side lock brakes & bolt on swivel locks and two (2) swivel casters with a bolt on swivel locks, with 8" diameter by 2" wide polyurethane on cast iron wheels capable of supporting a total weight of 5,000 lbs. (1,250 lbs./caster).