This is the optional Robinson Racing .8 Module GEN3 slipper unit the Traxxas E-Revo with the Mamba brushless system.
Includes: 68 tooth Steel Spur Gear, Aluminum Back Plate, Hex Slipper Pad, 5x13mm Ball Bearing, Aluminum Spacer, Four Cone Washers, Instructions and Decals
Requires: Hardened steel pinion gear
Note: 32 pitch and .8 module gears can be used together with no adverse effects such as increased noise or wear. This Slipper Unit is for the E-Maxx vehicles that have the round input shaft with the cross pin.