Current Overload, Short Circuits, Thermal Overload, DC Offset. Mono 1000 Watts Car Audio Amplifier gives you a wonderful in-car entertainment. High power, good sound quality, no distortion, give you a great hearing enjoyment. Light weight, handy and easy to install. Powerful bass. Wiring: 1. Speaker connection: amplifier board has a good piece of red and black wire welding can be accessed by a 4-8 Euro 100-150W bass or full-range speaker or speakers (red pick horn + , black pick speaker - is recommended to use 4 ohm 8-12 inch 45 core 100-170 magnetic bass ) 2. Power connection A. 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 and off ) B. Car no CD player : GND connected to the negative power of the car , + 12V and REM connected together in positive 12V car power ( + 12V can also be an indirect one with REM switch control amplifier switching function ) C. Directly with the battery (battery) connection : GND connect the battery negative , + 12V and 12V REM then the positive battery simultaneously. Specification: Model: PA-80D Product Name: Car Amplifier Subwoofer Type: Subwoofer Speaker Operating Voltage: 12V Frequency Response: 30Hz~280KHz Rated Power: 600W -Power: 1000W Impedance: 4-8 SNR: 105dBA : less than 0.1% Size: 23.5x15.5cm (LxW) knob color: random colors, don't accept the specified color colour: black Material: metal Package Contents: 2 x Car Audio Amplifier Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.