I wasn't entirely certain if this should be relegated to its own thread as it is several decades removed and an entirely separate prop, but here are (not very good) photos of Fluid Link K57 from Oxygen

http://tardisbuilders.com/index.php?topic=7623

Looks like it could be a repainted Car Plug, for cigs and stuff.

Does look to be something car-related to my eyes. Specifically it could be the end of a phone charger adapter for a car lighter socket. The side 'fins' possibly being the metal contacts.