Feature:
Power HD LF-20MG Servo (Metal Gear) 20kg/0.16s gives more powerful, Steering for RC Boat, RC Crawler, Truck, Buggy. 
Material: Middle Aluminum Casing With Plastic Top and Bottom
Color: Red and Black
Copper & Aluminum Gear

Specifications:
Output Gear: 25T
Torque(4.8V): 16.5 kg-cm (229.1 oz/in) 
Torque(6.6V): 20.0 kg-cm (277.7 oz/in)
Speed: 0.18 sec (4.8V) ‚ 0.16 sec (6.6V)
Operating Voltageï¼4.8 ~ 6.6 DC Volts
Weight: 60 g (2.12 oz)
Bearing Typeï¼Ball Bearing x 2
Motor Typeï¼DC Motor
Gear Typeï¼Copper & Aluminum
Operating Temperatureï¼-20~60
Working frequenceï¼1520μs / 333hz
Sizeï¼40.7 x 20.5 x 39.5 mm ( 1.60 x 0.80 x 1.55 in)