Traxxas 6487R 15-tooth machined steel pinion gear features 1.0 metric pitch and fits 5mm shaft motors (compatible with steel spur gears). Use Traxxas stock and hop-up replacement parts to get the most out of your Traxxas RTR vehicles. This product is made from high quality materials and designed for long-lasting performance. This is replacement hardware for use on Traxxas vehicles; consult your user's manual for exact parts listings.