Listing is for a set of four (4) Service Caster Series #20 casters, two (2) swivel bolt hole casters and two (2) swivel casters, with 4" diameter by 1-1/4" wide black polyurethane wheels. Supports a total weight of 1,200lbs (300lbs/per caster).When searching for a reliable and durable solution to your caster needs, consider Service Caster's Series 20 bolt hole polyurethane casters. The Service Caster Series #20 is ideal for light and medium duty material handling, carts, equipment, and shop projects. The bolt hole can accept a bolt or a customized stem, allowing for any type of mounting requirement. The zinc plated finish provides durability under any condition, while the non-marking, non-marring polyurethane wheels perform especially well on hard surfaces such as concrete, tile, and wood. All rolling on a finely crafted ball bearing design that will keep you moving forward. Service Caster is unsurpassed in quality, reliability, and excellent customer service. Count on us to move you forward.