Hot Racing differential Spool for the Traxxas 4-tec 2.0, Rally VXL, Rustler 4x4, Slash 4x4, Stampede 4x4, and Telluride 4x4. This is located in the differential case, and can be used front or rear to eliminate the differential action. This part is recommended for off-road use only. It is not recommended for on-road or high traction conditions. Features: - Black oxide coated CNC machined steel - eliminates differential action to aid traction and acceleration in low traction environments you will receive: - one (1) differential Spool shaft requirements: - Installation per Traxxas manual Specifications: - Length: 47.7mm - diameter: 9.5mm comments: - Replaces Traxxas 6882, output and spider gears - recommended for off-road and low traction conditions Only