Upgrade your Traxxas X-Maxx differentials with these spiral-cut, machined-steel ring and pinion gears. Spiral-cut design reduces vibration and noise while improving strength. The gears are sold as a match pair for each differential and fit the existing carrier and bearings. 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.