Listing is for a set of four (4) Service Caster Series #20 swivel casters, two (2) with top locking brakes, with 6" diameter by 2" wide polyurethane on cast iron wheel and roller bearings capable of supporting a total weight of 1,800 lbs. (450 lbs./caster). When searching for a reliable and durable solution for light and medium duty projects, consider Service Caster?s Series 20 polyurethane on metal wheel casters. The Service Caster Series #20 is ideal for material handling, carts, equipment, and shop projects. The non-marking, non-marring polyurethane tread performs especially well on hard surfaces such as concrete, tile, and wood, while the metal core wheel stands up to heavier loads with a stable and secure roll. Finely crafted with double ball bearing heat treated raceways, these versatile casters are ideal for a wide range of applications, such as dollies, platform trucks, warehouse carts and freight terminals. Or ensure a smooth and secure ride for food service carts, hotel housekeeping carts and industrial and commercial equipment. Even drywall carts, welding carts, and wall panel carts will be ready to roll on the Series 20, keeping you moving forward. Service Caster is unsurpassed in quality, reliability, and excellent customer service. Count on us to move you forward.