these wheels are similar to 179's go-ped wheels from 2005. you need to somehow attach a flange to get a sprocket on there and your good to go. the bearings in the go-ped wheels are amazing and I'm shire the Castor's are good too and much cheaper These look like a step in the right direction as far as affordable wheels that aren't samped out of plate, bolted together and fall apart when you use them on your robot.