Add some color and upgrade your Traxxas TRX-4 Rock Crawler drivetrain at the same time with our Billet Machined Center Drive Shafts. Our center drive shafts are drop-in upgrades for all TRX-4 chassis and is compatible with both the 12.8-inch wheelbase and the 12.3-inch wheelbase chassis. The Billet Machined Center Drive Shafts are sold in pairs