Original WWII German field phone connector cable that allows the standard FF33 to act as a small switch board. Every German field phone would have one of these cables stored inside next to the battery box; yes, that is what that little space is for. It seems that most phones are missing this cable. These cables connect across the front plugs on the FF33 and in lieu of a switch board multiple phones can be used to connect between lines. This one is tested and working. There is a crack in the black cover on one of the plugs. This does not effect the function.