Hi hope someone can help

I have just bought a 2003 W220 S350L.

It has a cd based Command system and a "curvy" cradle in the centre armrest with part number A220 820 1051. I have looked on various websites but cannot see this part listed other than an "accessory".

I think this is for a nokia 6310 but am unsure. I don't really want to upgrade the system to take a newer phone so hopefully somebody can confirm this before I try and get a second hand 6310 on the net?

Thanks in advance.