This is the MKS HV93I Micro Metal Gear Digital High Voltage Servo.

Specifications:
Dead Band: 0.001ms (Default)
Control System: +Pulse Width Control
Working Frequency: 760us / 560hz
Operating Voltage: 3.8~8.4 V DC Volts
Operating Speed (6V): 0.043 sec/60° degrees at no load
Operating Speed (7.4V): 0.035 sec/60° degrees at no load
Operating Speed (8.2V): 0.031 sec/60° degrees at no load
Stall Torque (6V): 25 oz/in (1.8 kg-cm)
Stall Torque (7.4V): 32 oz/in (2.3 kg-cm)
Stall Torque (8.2V): 36.11 oz/in (2.6 kg-cm)
Motor Type: Coreless Motor
Potentiometer Drive: Direct Drive
Bearing Type: Dual Ball Bearings
Gear Type: Chrome-Titanium alloy gear
Programmable: NO
Dimensions: 23x12x27.25mm (0.9x0.47x1.07 in)
Weight: 19.87g