These wheels are designed to work with the BR770182 and BR770183 gearmotors. They come in two sizes with diameters of 1.75" or 2", including the tire. The wheels are first laser-cut from 1/8" acrylic and then machined to have a groove for a 3/32" O-ring tire. The wheels securely press-fit onto the splined shafts of the GM6 and GM7 motors.
The wheels are packaged in sets of two plastic wheels and two O-rings. The wheels are engraved with the Pololu part number on one side; the wheels should be mounted with the engraved side facing the gearbox (the axle hole is slightly larger on that side, making press-fitting easier).