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 side lock brakes, 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). When searching for a reliable and durable solution to your caster needs, consider Service Caster’s Series KP30 polyurethane on metal wheel casters. The Service Caster Series KP30 is ideal for material handling, carts and industrial equipment. 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. Featuring a Kingpinless hot forged ASTM1045 steel design that increases caster durability and integrity, the series KP30 eliminates problems associated with kingpin failure due to severe shock loading. In addition, the Kingpinless design features 3/8” diameter HRC45 steel ball bearings which absorb thrust and load in severe environments. Lastly, Service Caster’s Series KP30 top plate casters are finely crafted with zinc plating, grease fittings, and 4 position notches to accept 4-position locks. These highly versatile casters are ideal for a wide range of applications, such as dollies, platform trucks, warehouse carts and freight terminals. Even drywall carts, welding carts, and wall panel carts will be ready to roll on the Series KP30, keeping you moving forward.