This is the MKS HBL880 Brushless Titanium Gear High Speed Digital Tail Servo.

Specifications:

• Dead Band: 0.0008ms (Default)
• Control System: +Pulse Width Control
• Working Frequency: 760?s / 560hz
• Operating Voltage: 6 ~ 8.4 Volts
• Operating Temperature Range: -10 to + 60 Degree C
• Operating Speed:
• @6V: 0.044 sec/60° degrees at no load
• @7.4V: 0.036 sec/60° degrees at no load
• @8.4V: 0.032 sec/60° degrees at no load
• Stall Torque:
• @6V: 113.87 oz-in (8.2 kg/cm)
• @7.4V: 140.26 oz-in (10.1 kg/cm)
• @8.4V: 155.39 oz-in (11.19 kg/cm)
• 360° Modifiable: NO
• Motor Type: Brushless Motor
• Potentiometer Drive: Indirect Drive
• Bearing Type: Dual Ball Bearings
• Gear Type: Metal Gears
• Connector Wire Length: 24.0 cm (9.4 in)
• Dimensions: 40x20x38.5mm
• Weight: 73.2g