Listing is for one (1) Service Caster Series #20 1-1/2 expanding stem swivel caster with a 3-1/2 diameter by 1-1/4 wide blue solid polyurethane wheel capable of supporting 300 lbs./caster. When searching for a reliable and durable solution to your caster needs look no further than the Service Caster Series 20 expanding stem solid polyurethane wheel casters. The Series #20 features an innovative expanding stem that can easily adapt to the inside diameter of the opening allowing for a secure fit in round or square tubes. Simply tighten the topmost knurled nut to compress the rubber for a snug fit. For added security further compress the rubber with a wrench via the nut under the swivel raceway. Finely crafted with a bright zinc plated finish heat-treated ball bearing raceway and a solid polyurethane wheel this versatile caster is ideal for work tables shop projects or any equipment with round or square tube legs. Service Caster is unsurpassed in quality reliability and excellent customer service. Count on us to move you forward.