Futaba S3157 Servo Digital Micro High-Speed/TorqueP/n: 1-F1616FEATURES:This is the Futaba S3157 Digital High Speed/High Torque Micro Servowith Universal Connector.Ideal for small electric planes and helicoptersINCLUDES:Futaba S3157 Digital High Speed/High Torque Micro Servo with universal connector 18x20mm, 4 arm servo horn (pre-installed) 20x40mm 4 arm servo horn 20mm diameter round horn.SPECIFICATION:Torque: 1.5 kg/cm @ 4.8V, 1.7 kg/cm @ 6.0V,Speed: .10 sec/60° @ 4.8V, 0.09 sec/60° @ 6.0V,Size: 22x11x23mm,Weight: 8.3g,COMMENTS:Not for use with gasoline powered models, large models or other models that require high torque. Using voltage higher than 6.0V or applying high load to the servo will shorten its life. Always use the servo horn specially designed for this servo. Do not use conventional servo horns. Excessive force or shock to the servo horn may damage the ultra mini precision gears inside the servo.