Traxxas 8297 replaces a remote locking differential on the TRX-4 Scale and Trail Crawler with a locked spool for extreme crawling. 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.