Your music and your phone calls, through your cassette player.
Plug DirectDeck's audio microphone cable into the headphone jack of your iPhone or smartphone. Then pop the DirectDeck cassette adapter into your tape player as you would any cassette. Your phone's audio plays through your car's stereo speakers. DirectDeck's inline mic lets you send and receive phone calls while you drive or ride, without taking your hands off the wheel or your attention off the road.