[Boatanchors] Help ID Strange BNC Type Connector

[Richard Solomon]

I picked up what looks like a Female to Female Chassis Mount BNC style 
connector
at the local Flea on Saturday.

What peaked my interest was that is was about 2/3 the size of a normal 
BNC, but
mechanically looked like a regular BNC.

The only markings on it were HHB 4603 (as best I could see).

Any ideas what this is ??

73, Dick, W1KSZ