This is the SH-1257MG Super Speed Metal Gear Mini Digital Servo.

Features:
The coreless motor and light weight design provides smoother, faster, and more efficient operation.
The metal case design not only looks awesome but also allows for cooler and smoother operating temperatures.
Metal gears form a solid framework for precise control and operation.
Supports digital and analog control signals
Ideal for rudder on 450 level helis, CCPM on 500 level helis, and steering servo on 1/12th scale cars.
Dimensions(mm):  35.0X15.0X29.2
Weight(g):  29.5
Speed(@4.8V sec/60):  .09
Torque(@4.8V oz-in):  26.4
Speed(@6.0V sec/60):  .07
Torque(@6.0V oz-in):  34.7
Gear:  Metal
Bearing:  2BB
Case:  Aluminum
25 Tooth Spline

Technical Specs

Dimensions(mm):  35.0X15.0X29.2
Weight(g):  29.5
Speed(@4.8V sec/60):  .09
Torque(@4.8V oz-in):  26.4
Speed(@6.0V sec/60):  .07
Torque(@6.0V oz-in):  34.7
Gear:  Metal
Bearing:  2BB
Case:  Aluminum
Running current (at no load):  100 mA @ 4.8V
Running current (at no load):  120 mA @ 6.0V
Stall current (at locked):  4000 mA @ 4.8V
Stall current (at locked):  5000 mA @ 6.0V
Idle current (at stopped):  5 mA @ 4.8V
Idle current (at stopped):  5 mA @ 6.0V
Limit angle:  200°±10°
Connector wire gauge:  ＃22 AWG
Connector wire length:  250 ±5 mm
Horn gear spline:  25T
Control system:  Pulse width modification
Amplifier type:  Digital Controller
Operating Travel:  100° (when1000→2000 μsec)
Neutral position:  1500 μsec
Dead band width:  3 μsec
Rotating direction:  Counterclockwise (when1500→2000 μsec)
Pulse width range:  800→2200 μsec
Maximum travel:  Approx 130°(when900→2100 μsec)

Super Speed Metal Gear Mini Digital Servo