The XeroGear Night Fly System Light Controller. The controller allows you to completely control your Night Fly System from your transmitter! Using this controller you can Dim, brighten, and turn off your Night Fly System all from your transmitter and while IN flight. The best part of the controller is it is 2s and 3s Li-Po compatible. This controller turn your lights off with your receiver and save your LiPos from over discharging. You can use multiple controllers to create special effects while in flight!