This is the JR Sport RT88 Retract Servo.  This servo has a universal connector that works with JR, Hitec, Futaba, and Airtronics.

Specifications:
Size Category: Specialty
Type: Analog
Torque: 88 oz/in @ 4.8V
Speed: 1.12/160 @ 4.8v, .90/160 @ 6v
Dimensions (WxLxH): 1.74 x .92 x .88 in
Weight: 1.15 oz
Gear Type: Nylon
Application: Retractable Landing Gear