This is the Savox SA-1230SG Tall Digital "Monster Torque" Steel Gear Servo.

Features:

• Combines leading edge technology with super high 12 bit (4096) resolution and unique steel gears.
• Super light-weight.
• Coreless motor provides extremely high speed, incredible efficiency, and low power consumption.
• Extremely strong unique steel gears ensure long-life and durability.
• The full aluminum case design not only looks good but also allows for cooler and smoother operating temps.
• Servos are environmentally friendly.
• Ideal for giant scale aircraft, monster truck, 1/8 scale.