This is the Futaba BLS255HV High Voltage High Speed Digital Servo. FEATURES: Ideal for swash plate control on flybarless CCPM helis Dual bearings and metal gears for smooth, long-lasting operation Handles up to 2S LiPo battery power One year limited warranty through Hobby Services beginning at date of purchaseINCLUDES: Futaba BLS255HV Servo 0.83" (21mm) Diameter Round Horn 1.8" (45mm) Diameter Round Horn 1.6" (38.5mm) Diameter 4-Point Horn 1.2" (32mm) Diameter 6-Point horn Mounting Hardware REQUIRES: Installing in heli, connecting linkage and connecting to receiver SPECS: Speed: 0.10 sec/60° at 6.0V 0.08 sec/60° at 7.4V Torque: 147.2 oz/in (10.6 kg/cm) at 6.0V 166.7 oz/in (12.0 kg/cm) at 7.4V Size: 1.57 x 0.79 x 1.45" (40 x 20 x 36.8mm) Weight: 2.12oz (60g) Power Supply: 6.0 - 7.4V DC COMMENTS The BLS255HV is designed for high torque/high speed applications.Very high current drain is normal at startup. Always use a 6V - 7.4V battery.