This is the Hitec HS-7245MH Coreless Motor High Torque Digital Mini Servo.
FEATURES: Ideal for elecric powered 500 class helis 1/12-1/18 scale cars, gliders, electric powered airplanes, electric and glow powered boats 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-7245MH 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: 0.13 sec at 60° 0.11 sec at 60° Torque: 72.21oz-in (5.2kg-cm) 88.88oz-in (6.4kg-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: .17 LBS.