What kind of EV mic is this?

[teainthesahara]

Found this mic (EV stereo cardioid 7020) in my girlfriends basement. The top and bottom barrel swivel so the capsules inside (which are metal and large, pretty much filling the whole basket) can face opposite directions. I want to try this mic out, but im not sure what to make of the input connector on it - is there an adaptor for this? Anyone know the history of these things?

Thanks,
T