This is the Ace RC S1807MG Standard 2BB Metal Gear servo.

FEATURES: Wide usage in cars, boats or planes that require a standard
            high torque servo
          Two ball bearings
          Universal connector
          Metal gears
          4M gear type
          18 month warranty

INCLUDES: One S1807MG high torque servo, two 1.7" diameter serov horn,
            4 eyelets, 4 rubber grommets, 4 nylong locknuts

SPECS:    Dimensions: 1.59 x .79 x 1.49" (40.4 x 20 x 37.9mm)
          Weight: 1.77oz (50.1 g)
          Speed: 0.21 sec/60° @ 4.8V
          Torque: 95.8 oz-in @ 4.8V (6.9kg/cm)
          Power Supply 4.8V or 6.0V

                                                                     JAW 2/1/11