Power HD LF 13MG, standard size digital servo. FEATURES: Water Resistant, not water proof. Specs:Torque(4.8V): 10.5 kg-cm (145.8 oz/in) Torque(6.0V): 13.0 kg-cm (180.5 oz/in)Speed: 0.15 sec (4.8V)‚ 0.12 sec (6.6V)Operating Voltage: 4.8 ~ 6.6 DC VoltsWeight: 60 g (2.12 oz)Bearing Type: Ball Bearing x 2Motor Type: DC MotorGear Type: Copper & AluminumWorking frequency: 1520μs / 333hzSize: 40.7 x 20.5 x 39.5 mm ( 1.60 x 0.80 x 1.55 in) Servo Arm: 25TNote: When the digital steering gear is subject to resistance will be issued a continuous creak current sound, the greater the resistance sound the more loud, this is a normal phenomenon.