THIS KIT IS FOR THE STOCK TRAXXAS AXLE CARRIERS. THE DIFFERENCE IS THE SIZE OF THE OUTER BEARING.8mm heat treated aircraft steel axles with 3mm hardened steel cross pins. The cross pins are locked into place with a 5mm set screw through the front of the axles, similar to the time proven design found on the 1/8 scale nitro buggies. The axles are designed like the stock REVO/SLAYER axles, and plug right into the stock REVO/SLAYER driveline yokes. Items included in our 8mm axle kit: Qty-4 heat treated steel 8mm axles. Qty-4 Hardened steel 22mm X 3mm cross pins. Qty-4 5mm set screws. Qty-4 8mm X 12mm X 3.5mm rubber shielded bearings (bearing adapters included to fit the stock axle carriers Part # 5334R).