Bring all of the sound of your onboard audio system right into your helmet with the Sena 20S Helmet Clamp Kit. The adapter cable with 7-pin DIN plug connects the onboard audio system to the helmet clamp and allows users to listen to the onboard audio system, including FM radio and GPS navigation. The CB radio retains full functionality via use of the integrated PTT switch/button and clamp kit microphone. When paired up with a Sena 30K, 20S or 20S EVO main module, all sounds - CB radio, GPS navigation, and FM radio - from the onboard audio system can be mixed with Sena sound sources, including intercom, MP3 music, and phone.