The Southerland Wheel Kit comes with one wheel, two bearings, two washers and nylon nut. This delrin wheel is designed to fit both Misumi aluminum extrusion and 80/20 extruded aluminum. The black delrin plastic material makes a great long lasting wheel. Delrin is also referred to as POM or acetal plastic. The delrin wheel kit comes with two flange bearings and m5 cap screw. 3D Distributed has a wide selection in delrin wheels for all applications. Our wheels can be compared to Inventables and Openbuilds V Wheels.