This is an optional Traxxas 2075X Digital High Torque Metal Gear Waterproof Servo.
The 2075X waterproof High-Torque Metal Gear Servo combines commanding steering authority with the superior durability of all-metal gears for the ultimate driving experience.
Features:
All metal gears with ball bearing support
Digital High-torque 125 oz-in.
Transit Time .17 sec/60°
L=55 mm, H= 43 mm, W=21.5 mm