Tower Pro MG90S Servo Motor with Metal Gear
The MG90S is a metal gear servo motor commonly used in RC applications like RC cars, RC boats, RC helicopters, Airplane etc. It has a stall torque of 1.8kg/cm when operating on 4.8V and about 2.2kg/cm when operating on 6V.
The motor operates between 4.8V to 6V and weighs about 13.4 grams. The metal gear provides ruggedness for the motor and increases the life time of the motor since the gears will not wear out.