For added performance, we recommend the REEFS 8.4V EZ-BEC For programming, the USB Link is required. Features: High Torque High Speed Brushless SERVO or WINCH Comes as SERVO out of the Box, can be changed to WINCH with the REEFS LINK and Software. BUILT-IN PREPROGRAMMED WINCH CONTROLLER Internal Steel Gears / All CNC Aluminum Casing Magnetic Angle Sensor Pulse Width Modulation Control 4 Pole Brushless Motor REEFS LINK required for Programming BEC Not Req. Recommended for max performance Specifications:SUBMARINE WATERPROOF: 7 Point Seals w/ GRAY HEAT SINKVoltage: 4.8V 8.4VBearing Type: 4 Ball Bearings / Weight: 2.99ozDimension: 1.57 x .79 x 1.5 (LWH)Torque: 720oz @ 6v/ 830oz @7.4v/ 940oz @8.4vSpeed: .13sec @6v/.12sec @7.4v/.10sec @8.4vSpline: 25T / Dead Band Width: 2¦ÌsUnload Current: 460mA @ 4.8V / 500mA @ 6.0V / 540mA @ 7.4V / 580mA @ 8.4VLoad Current: 5000mA @ 4.8V / 5800mA @ 6.0V / 6800mA @ 7.4V / 7400mA @ 8.4V WARNING: This product can expose you to chemicals, which are known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.