This is a Hot Racing Hardened Steel 46-Tooth Mod-1 Spur Gear for the Traxxas X-Maxx and XO-1.
Overall Diameter: 48mm
Gear Face Width: 8mm
1x 46T, 1 Mod Steel Spur Gear
Do NOT use the pin system for setting the X-Maxx gear mesh. Instead, manually set the gear mesh without the pins. Refer to the Traxxas manual for instructions (ref. pg.22 - Adjusting Gear Mesh):
With the pins removed, use the four 4x16mm button-head cap screws on the bottom to set gear mesh. Loosen the four 4x16mm button-head cap screws. Cut a narrow strip of notebook paper and run it into the gear mesh. Slide the motor and pinion gear into the spur gear. Tighten the four 4x16mm button head cap screws, and then remove the strip of paper. You should be able to run a fresh strip of paper through the gears without binding them.