The Connects 2 CTVFOX002 is suitable for late Ford cars which have the stereo which incorporates the central volume control as stated in the picture below.
The Connects 2 CTVFOX002 will NOT work with Sony units!
It will allow you to connect an external audio source to your original factory head unit via the original CD changer socket on the rear of your unit. The interface has a pair of RCA input sockets and also comes with a 3.5mm to RCA adaptor lead which will plug into the head phone socket on typical mp3 players etc.