Our T-harnesses let you integrate an additional device such as an aftermarket bluetooth kit into your car's factory radio and it's wiring. This allows your aftermarket Blue tooth kit to work with your car's speakers directly when on a phone call and revert back to the stereo when the phone is not in use. CT10KI01 Carnival 2003-2005 Cerato >2009 Optima >2006 Rio 2008> Sedona >2005 Sorento 2002-2007