Feature:HIFI power bass amplifier. Enjoy the top music when driving all the times. Enjoy a wonderful journey. Fit for all 12V vehicle. Specification: Voltage: 12 V Max Power: 180 W Actual Power: 150 W Impedance: 4 Sensitivity: 75-90DBDistortion: 0.01% (human ears almost can not hear) Speakers: 6 inch/ 8 inch/ 10 inch/ 12 inch Treble: Unlimited Dimensions: 16x 8.2x 15cm Power Connection:1. Car has a CD player: GND then negative vehicle power ; 12V 12V power supply connected to the car s positive;REM CD player connected to the control line (so the CD player can directly control the subwoofer amplifier on & off )2. Car no CD player: GND connected to the negative power of the car, + 12V & REM connected together in positive 12V car power (+ 12V can also be an indirect one with REM switch control amplifier switching function ) ;3. Directly with the battery (battery) connection: GND connect the battery negative, + 12V & 12V REM then the positivebattery simultaneously. Package Included:1 X HIFI Car Amplifier