... 3D Acceleration SensorDescription:- 100% brand new free flight controller, four axis Free Flight FF Auto Balance Controller,it can be used ... and Six channel PWM output- Adopts three axis digital gyroscope and three axis digital accerleration sensor.- Auto-balance,quadcopter X ... down 3,accelerograph 4,Heading Direction 5,Remote control calibration( Switch channel) 6,PTZ pitch angle 7, PTZ pitch angle ...