Experience the perfect blend of nostalgia and modern technology as you relive the charm of cassette decks while enjoying the convenience of your latest music playlists Have a cassette player in your car and want to play back music from your MP3 player? Here's a simple solution. If your device has a 3.5 mm. Output, This audio cassette adapter you can hook you up! Simply plug the cassette adapter into your car's cassette deck, then plug your device into the attached cord! Playback through your car's audio system will be in stereo.