This is a 6in Traction Wheel designed for use in FIT Robotics Competitio on robot drive systems. It is intended to be used in combination with a length of 1in wide traction tread material, just as you would with any standard traction wheel, such as those available from VexPro or Andymark, but at a reduced weight. These wheels use the standard 1.875 in mounting hole pattern found on most FRC wheels. The axle hole can accommodate up to 2 standard 1.125" flanged bearings which mount flush to the surface of the wheel, or VexPro "VeaHubs". Tread can be attached with 8-32 screws and nuts using the included mounting holes (which also makes changing tread without removing the wheel from the robot easy). Note that this design is similar to my Ultralightweight 6in wheel, the main difference being this veion should be easier to print and more durable, at the cost of a slightly longer print time and higher weight. DO NOT USE POP-RIVETS TO ATTACH TREAD TO THESE WHEELS! These wheels have been proven to be durable for use at up to 3 district events (during the 2018 season) before any replacement is necessary. Depending on the application, you may see some degradation of the edge of the wheel rim where the tread sits between over time, this is normal and purely aesthetic. Wheels should be replaced if any damage is found in the areas of the wheel that directly support the tread or the mounting holes. Total weight using eSUN PLA material: ~0.496lbs per wheel (wheel only, no tread or hardware included)