This is the Futaba S3051 HV High Voltage High Torque Standard Servo. FEATURES: Digitally enhanced microprocessors cut in half the response time from transmitter input to servo reaction Standard size servo offers high torque and high speed One year limited warranty through Hobby Services beginning at date of purchase INCLUDES: Futaba S3051 HV High Voltage High Torque Standard Servo with 0.83" (21mm) Round Horn, 1.4" (35.2mm) Round Horn 1.5" (38.5mm) 4-Point Horn, 1.2" (31.9mm) 6-Point Horn, Mounting Hardware and Instructions REQUIRES: Installing in model, attaching linkage and plugging into receiver SPECS: Speed: 0.21 sec/60° @ 6.0V 0.19 sec/60° @ 6.6V 0.17 sec/60° @ 7.4V Torque: 132.0 oz/in (9.5 kg/cm) @ 6.0V 138.9 oz/in (10.0 kg/cm) @ 6.6V 145.8 oz/in (10.5 kg/cm) @ 7.4V Size: 1.57 x 0.79 x 1.50" (40 x 20 x 38.1mm) Weight: 1.73 oz (49 g) Power Supply: 6.0 - 7.4V DC Hron Screw Size: 3x8mm jxs 08/22/11 ir/jxs