Take a Solarbotics GM2/3/8/9 style gear motor, add a spanky LARGE diameter wheel, and you've got a powerhouse combination that can take on any regular servo!

Solarbotics designed this injection-molded ABS wheel to fit the double-flat output shaft of the GM series gearmotors. Gone are the rubber bands, replaced by molded-on thermoplastic silicon tires with superior traction & wear characteristics!

What is really cool with this new design is the inclusion of a 64 strip pattern designed to match the popular "Wheel Watcher" optical encoders. Just paint in every other stripe pocket, and you're ready to go!

Need stats: Ok, here you go:
The hubs dimension out at 69mm (just under 2-5/8"), by 7.62mm wide (0.3").
Size: 6.8 x 0.7 x 5.0 cm