I traded someone for this module. I have a new Bluetooth phone interface, for select E, CLS, C, CLK, ML, R, GL, and G. There is no reason to worry either if your vehicle is prewired, this interfaces on the fiber optic MOST system. If you have any questions PM me

here is a link to the interface. I will say this is the one of the best products I have seen from this company or for a Mercedes in general

LINK PDF