S0010008 MKS HBL669 High Voltage Brushless Tail Servo 

Specification
Torque: 4.2 kg-cm (58.33 oz/in)(6.0V)
Torque: 5.1 kg-cm (70.82 oz/in) (7.4V)
Speed: 0.05 s (6.0V)
Speed: 0.04 s (7.4V)
Weight: 63 g (2.22 oz)
Dimensions：40 x 20 x 40 mm ( 1.57x0.79x1.50 in)
Operating Voltage：6.0 ~ 8.4 V DC Volts ( 2S Lipo un-regulated )
Working frequence：760μs / 560hz
Dead band：0.0005ms (Default)
Bearing Type：2BB
Motor Type：Brushless Motor
Gear Type：Chrome-Titanium alloy gear