This Yeah Racing Rear Axle Housing is an optional accessory for the Traxxas TRX-4 rear axle. It features a cast/machined finish, with an additional Titanium coating for even more durability. High shine silver edges add that extra bling, while original TRX4 diff covers fit no problem. This package does not include the axle internals or diff cover, and will require those parts to finalize assembly. Rear Axle Housing Weight: 124g