GC301-Gyro for RC Cars, It is a device using gyro sensor and software algorithm to adjust steering output, providing you with a more stable and controlled driving experience. The Gyro's heading hold effect manages steering output by automatically keeping the car's tires aligned in the direction you choose. It will also precisely maintain car direction regardless of the amount of traction of the track or outside force apply to the car. With heading hold, the car is more maneuverable and controllable. Features Automatic corrective steering action for RC cars GC301 gyro allows you to drive the RC car toward a given direction and take precision turns at high speeds. This makes the vehicle more manageable, controllable and stable. ?Remote gain function You can adjust gain from the transmitter CH3 by using the remote gain function. Gain can also be adjusted with the trimmer on the GC301.