This is the Hitec HS-7235MH Coreless Motor High Voltage Digital Mini Servo.

FEATURES: Ideal for mid-size gas and electric airplanes, 500-550 electric helis 1/12 scale on-road racers, and 1/18 scale rock crawlers Coreless motor optimized for 7.4V operation Heavy-duty metal gear train with dual ball bearings Water and dust resistant G2 high resolution digital amplifier with MOSFET drive Two year limited warranty through Hitec beginning at date of purchase

INCLUDES: Hitec HS-7235MH Servo 1.3" (34mm) Double Arm Horn 1.2" (30mm) Single Arm Horn 0.94" (24mm) Round Horn 1.2" (31mm) Four Point Horn 0.87" (22mm) Aluminum Single Arm Horn Mounting Hardware

SPECS: 6.0V 7.4V Speed: 0.09 sec at 60° 0.08 sec at 60° Torque: 49.9oz-in (3.6kg-cm) 61.1oz-in (4.4kg-cm) Weight: 1.2oz (34g) Size: 1.28 x 0.66 x 1.29" (32.4 x 16.8 x 32.8mm)

COMMENTS: A note on coreless motors-a conventional servo motor has a steel core armature wrapped with wire that spins inside the magnets. In a Coreless design, the armature uses a wire mesh that forms a cup that spins around the outside of the magnet. This arrangement is much lighter resulting in smoother operation and faster response time.  

BOX DIMENSIONS: 3.00" W. X 1.38" H. X 3.75" L. BOX WEIGHT: .18 LBS.