This Alloy Spur Gear Mount is a heavy duty option part that replaces the stock plastic mount on Sprint 2 cars. The metal mount keeps the spur gear securely mounted and greatly reduces the chances of the spur gear stripping. It's highly recommend for use with high powered motors such as the Flux brushless system. This is also a replacement part for the Sprint 2 Flux car, built to precise factory specifications for a perfect fit.