The adapter is called a line level converter (i believe) and Loco is correct, you will install it to your rear speaker channels and run the power from a switched on power wire.(meaning when vehicle is on the amp will get power, when off no power) you can find one going to your radio and possible coming from your radio(you just have to look hard enough and probe the wire)

--Joe


1999 Contour SVT ~ Black w/Tan Current Mods: Fog light rewire, 20% Tint, SVT Banner,Rockford Fosgate RFX-8340, 2-12" Bostwick SPL Subs & Audiobahn 600x2 Future Mods: Knauberizing it, lowering