1.This machine uses voltage is DC 12V, negative ground system,pre-installation required to confirm whether your car's electrical system of this type.2.This unit with automatic antenna subwoofer separately powered.3.It must be connected with the wire of wiring diagram, if connected incorrectly,it may cause malfunction or damage to the vehicles electrical system.4.The speaker leads (-) must be connected to the speaker terminal (-),do not receive the body or interconnected to each speaker.5.Do not block vents or heat sink,so as to avoid overheating and damage to the machine.Note. The left and right bracket screw can not exceed 8MM, otherwise it will damagethe machine components.Wiring diagram4