Listing is for a set of four (4) Service Caster Series #20 1-7/8" expanding stem 316 stainless steel swivel casters, two (2) with total locking brakes, with 3" diameter by 1-1/4" wide maroon polyurethane wheels capable of supporting a total weight of 1,000 lbs.. Mounting options include top plate, bolt hole, expanding stem and standard and metric threaded stem sizes.