... motor drive unit 3, Rolling code 4, Safety auto-Reverse ,roller door operator garage door opener 1, Inpout Voltage : AC230/110V selectable2, ... unit automatically,reverses should the downward movement of the door be restricted. The overload force is adjustable13, photo ... function19, Easy installation20, OEM, ODM is welcomed. roller door opener, roller door operator, garage door opener dc motor