The GA-410 is a dual-gain, advance featured, performance tail lock gyro specifically designed for 3D model helicopters.   Features Sensor : Quartz vibration sensor Control system : AVCS (Angular Vector Control System) Dual-Gain system : Tail lock mode / normal mode DIR function : Use the reverse switch on the gyro to set the output direction Limit function : Use the travel rotary knob on the gyro to set the servo travelling range.   Specifications Operating voltage : DC 3.3 ~ 9.0V Operating current : 7mA Operation temperature :  -5C to 60C Dimension : 27x27x20mm Weight : 15g