This is Robinson Racing 72-Tooth Steel Spur Gear with Ball Bearing. It is for the Traxxas T-Maxx .15, 2.5, and Nitro Rustler. This is much more durable than the stock gear. It replaces the stock #4472 from Traxxas.
INCLUDES: One 72T steel spur w/bearing pre-installed
SPECS:Thickness: 4mmDiameter: 60mm
Fits Traxxas T-Maxx .15, 2.5, and Nitro Rustler