... into your car stereo changer port(Usually located behind the radio),Plug in USB disk/SD card or aux in devices ... same as multi CDs;7)Compatible with most OEM car radio:AUDI VOLKSWAGEN,SKODA,TOYOTA,HONDA,MAZDA,SUZUKI and after market ... car radio:SONY,PANASONIC,ALPINE,CLARION,PIONEER,BLAUPUNKTCompatibility for aftermarket radio Alpine(M-bus) Charmlink car digital ...