Originally designed as capstan roller for cassette tapes (remember those?), they’ve found a second life as high-performance wheels for tiny robots and in our own SolarSpeeder kit. This version of the wheel is 9mm instead of our standard 10mm wheels.

 Specifications:

• 9mm OD
• 1.5mm ID
• 7mm wide
• Nylon hub

If you’re planning to use these as coasting wheels, they roll quite nicely on standard 0.055″ music wire. And our PRet plastic retainers do a good job of holding them in place.