This is a pack of two optional Hot Racing Front Steel CV Splined Drive Shafts for the Traxxas UDR. Hot Racing optional upgrade heavy duty front splined star drive CVD axle kit for the Traxxas Unlimited Desert Racer. Features: Completely replaces factory dogbone-style axles from the differential all the way out to the wheel hex CNC machined #45 hardened carbon steel CVs, drive hub, male slider spline, and stub axle CNC machined aluminum slider tube Blue anodized aluminum pin capture rings with rubber o-rings to prevent movement Specifications: Collapsed length, overall: 154mm Extended length, overall resulting in zero shaft engagement: 164mm Collapsed length, wheel pin to outdrive pin: 138mm Extended length, wheel pin to outdrive pin resulting in zero shaft engagement: 148mm Weight/pr: 132g Needed To Complete: Installation to drive assembly Reuses drive pins Recommended to maintain CV joint and shaft spline with grease Recommended to medium thread lock on screws threading into metal NOTES: Replaces Traxxas axle parts: TRA8551 (drive cup & screw), TRA8550 (dogbone), TRA8553 (stub axle), TRA8554 (CV joint)