JMT 70a 22.2v ESC Speed Controller for Trex 500 Rc Helicopter Heli 3d Compatible with Lithium and Nickel battery types.(Lithium-lon/Lithium-polymer or Nickel Metal Hydride / Cadmium) Extreme low output resistance, super current endurance Multiple protection features:low-voltage cut_off protection / throttle signal loss protection Before producing, the manufacturer have set up the program, the ESC do not need additional program. This ESC do not have the English instruction.