This is a printable plastic wheel for use with the Solarbotics GM-series (i.e. GM2, GM8, etc.; see http://www.solarbotics.com/products/gm8/) motors and compatible with the Solarbotics RW2 ( http://www.solarbotics.com/products/rw2_t/ ) tires.I needed a wheel that would fit on the double-flat output of the GM-series motors and also work with the tires of the RW2 wheels for a Sumobot. I designed these in OpenSCAD for printing on a MakerBot.Download the STL files for printing immediately, or the SCAD files if you feel like tweaking measurements or shapes. Generate the gcode in ReplicatorG (for the MakerBot) or your program of choice. Print out the wheel, trim it up, and off you go!