High Precision 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 chose. 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.