Extreme heavy-duty front 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. A unique splined telescoping design delivers full-range articulation, so there is never a need to limit suspension travel. They are made by Traxxas, for Traxxas so you can always count on easy installation and the perfect fit. Axle carriers are for use with the 9080-series upgrade kit only and will not fit standard suspension parts.