Nice sign you have there Hoarder,,it brings alot of memories back to me from when i was a young kid..I think Rusty Tins is correct in what he says,in the fact that it was a double sided sign,abit like the Craven A underground shaped one,,but believe it or believe it not there is or at least i can say ive seen the same sign with a dark blue backgound and no black rim round it sinlge sided one back in the 70s at B/HAM rag market...Thanks for showing..