Car Audio Adaptor for Apple iPhone 4 16GB / 32GB Now whether you are going down the block or cross-country, you will have plenty of music for the whole trip with this adapter Connect your CD Player / MiniDisk Player / iPod to your car stereo through your car's in-dash cassette player Cassette-shaped Interface inserts into your car's tape deck. Mini-plug inserts into your iPod / CD Player / MiniDisk Player headphone jack Silent mechanism reduces mechanical noise on the road Spring-loaded cassette head helps maintain contact with cassette player's head for clear sound