OEM iPhone kit comprises of an interface to allow direct connection of an iPod, iPhone to head units. Simply plug the kit together and into the back of the car radio, connect your iPhone/iPod and that's it! Once fitted, audio from the iPhone/iPod will output through the original car audio system, with volume controlled by the stereo (or steering wheel stalk controls where fitted). The original car radio disc track seek buttons can also be used to select tracks within the currently selected iPhone, iPod playlist folder.