... WMA decoder Building in Amplifier chips Widely extend external audio sources, like PC, MD, PSP, GPS ... Free accessores:usb extend cable, 3.5 line audio cable,usb reader,user manual: Installation Guide:The ... the carPlug the Digital Music Changer into your car stereo changer port(usually located behind the radio)Insert ... MP3 and Aux in.Install illustration: car audio usb interface CE,FCC,RoHS approved