This is a robot wheel made to fit one of those "cause of the week" wrist bands, and generated with the Highly Configurable Wheel (One Wheel To Rule Them All) at http://www.thingiverse.com/thing:21486. Credit for the idea of using one of those wristbands (which I think was a fantastic idea and seems to provide excellent traction) goes to AUGuru. I just tweaked some of the settings and printed it. Unfortunately, I forgot to hit Ctrl-S before I closed down OpenSCAD after exporting the STL, so I don't know exactly what settings I used, but the wheel diameter measures 68mm and I used a 6-spoke diamond pattern with concavity and the "slots" option for tread. It was modeled for a 4mm motor shaft and a 3mm set screw. The print quality here is not very good, and I think I'll have to use an M2.5 because I can't drill out the set screw hole, but other than that the tire holds very well and the traction is excellent. 1) Print. 2) Stretch wristband around wheel as a tire. 3) Install on robot. 4) Run for your life because one-wheeled robots can be pretty mean.You can tweak the size and design by modifying the original OpenSCAD file. This one is quite rigid and string, using 3.38m of 3mm filament with 2 perimeters, 2 solid layers, and 20% honeycomb infill.