This is the Savox SV-1272SG Digital "Monster Torque" Metal Gear High Voltage Servo.

Features:

• Extremely powerful for its size pushing 416 oz-in torque @ 7.4V.
• Super strong and precision made unique steel gears provide durability that will survive heavy use.
• Coreless motor delivers smooth, fast, and efficient performance.
• Special design for high voltage 2S LiPo operation.
• Servos are totally green – from materials to production, these servos are environmentally friendly.
• Ideal for large-scale airplane, jet, and 1/5th scale surface

Specifications:

• Dimensions: 40.3x20.2x37.2mm
• Weight: 63g
• Speed:
• @6.0V: .13 sec/60
• @7.4V: .10 sec/60
• Torque:
• @6.0V: 319.4 oz-in
• @7.4V: 416.6 oz-in
• Gear: Unique Steel
• Bearing: 2BB
• Case: Aluminum
• Spline: 25 Tooth