BlueTooth A2DP + USB Flash Drive Car Stereo Adapter Interface for select Audi For select Audi vehicles Add Bluetooth Conversation + music streaming to the factory radio USB connection input for USB flash drive use only Works with all factory radios with the cd changer port. Radio must be external cd changer capable- back of radio has to have cd changer port. If it doesn't then there won't be a port for this connector to connect to so it will not be compatible. Any device connected to cd changer port has to be disconnected. USB port is for USB flash drive only. Works with the following vehicles: Audi: 1999-2005 A2, 2001-2007 A3 (no navigation), 1998-2005 A4, 2006 A4 (no navigation), 1998-2004 A6, 1998-2003 A8, 2000-2007 TT (no navigation)