Spur Gear, 54-tooth, Steel (Wide-face, 1.0 metric pitch)
Overview:
Traxxas spur gears let you fine-tune the performance of your Traxxas model. Changing gear ratios can help balance acceleration and top speed for different running conditions. Please consult your owner's manual for more information on recommended gearing options for your specific model.
This is an accessory part for the following Traxxas models:

X-Maxx: TQi Traxxas Link Enabled 2.4GHz Radio & TSM (Model# 77086-4)
E-Revo VXL Brushless: TQi Traxxas Link Enabled 2.4GHz Radio & TSM (Model# 86086-4)
Maxx: TQi Traxxas Link Enabled 2.4GHz Radio & TSM (Model# 89086-4)
Maxx: TQi Traxxas Link Enabled 2.4GHz Radio & TSM (Model# 89076-4)
XO-1: TQi 2.4GHz Radio System, Traxxas Link Wireless Module, & TSM (Model# 64077-3)