Used but in great condition Pac Audio Ap4-ch41 audio interface. Make aftermarket audio connections a breeze with factory plug and play hook up and gives you 3 sets of rca outputs with a flat clean signal and control knob for sub volume control and remote turn on as well for your amplifiers. Also has the option to connect to a pc and set up and change your bass mids and treble frequency and Q curves as well as other options depending on your car.
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