What is this part in my '81 380SLC
 

I found this strange part with its own wire harness behing the passenger side kick panel. It doesn't seem to be a Mercedes part; if somebody could confirm that it is better to unscrew it and throw it to the trash, or if it's actually something valuable to the car, any response will be appreciated.

http://i678.photobucket.com/albums/v...r/underslc.jpg

Its appears to be an after market phone speaker - old school. Not OEM.