General Information: 1. This device's DC voltage is 12V.Please check the DC voltage on your car before you install the device. 2. In order to avoid electrical short-circuit,please connect ground wire with battery negative. 3. Always ensure when installing wire connection is done properly. After the wure connection is finished,then you connect negative wire on the unit with the negative on your battery. 4. In order to avoid electrical short-circuits,please maintain the wire insulation. 5. In order ro avoid knock down other object,please affix all of the wires. 6. When the fuse is blown,please replace with a fuse which is the same specifications. 7. Please use high quality loudspeakers of 4~8 Specifications: Entire: SNR: 65DB Ferquency response: 20Hz~20KHz Output: Audio output Tone control: Bass 100Hz Terble 100Hz Power anplifier: Output: loudspeaker output Loudspeaker impedance: 4~8 Maximum power output: 4x50W