This is the Savox SW-0231MG Waterproof High Torque STD Metal Gear Digital Servo. 

The SW0231MG is a budget friendly waterproof digital servo with great torque for many applications. This brushed servo features a speed of .17 and 208.0 oz-in of torque 6.0V. It combines leading edge technology with super high 12-bit (4096) resolution and metal gears for your greater precision when dodging puddles. This is a great upgrade if your looking to drive your RC vehicle in any condition...rain, sleet, or snow. 
Features:
● Combines leading edge technology with super high 12 bit (4096) resolution and metal gears.
● Waterproof.
● Brushed motor
● Extremely strong metal gears ensure long-life and durability.
● Our servos are totally green – from materials to production, these servos are environmentally friendly.
● Ideal for RC cars, trucks, buggies, and boats.

Dimensions(mm): 41.8x20.2x42.9
Weight(g): 66
Speed(@6.0V sec/60): .17
Torque(@6.0V oz-in): 208.0
Gear: Metal
Bearing: 2BB
Case: Plastic
25 Tooth Spline
IP Rating: 67
Frequency: 200-250hz
Pulse Width Frequency: 1520

Specification:
Dimensions(mm): 41.8x20.2x42.9
Weight(g): 66
Speed(@6.0V sec/60): .17
Torque(@6.0V oz-in): 208.0
Gear: Metal
Bearing: 2BB
Case: Plastic
25 Tooth Spline