Extreme Heavy Duty Rear Driveshafts TRA9052RDetails: Extreme heavy duty rear steel CV (constant velocity) driveshafts feature larger 6 mm stub axles to work specifically with the Extreme Heavy Duty Upgrade Kit. Designed for intense high power applications, these shafts are built to withstand the brutal torque from the 540XL motor and the massive grip of huge Sledgehammer tires. Traxxas unique, splined telescoping design delivers full range articulation, so there is never a need to limit