This is a Transco brand 15KV/30ma neon sign transformer used to power the original junk box coil. I bought it new from an on-line dealer in the US. Note the safety gaps on each bushing made from small metal mending plates with machine screws passing through them. I put a small square of Aluminum tape on the case under each gap so the spark wouldn't mar the paint. Although this is a 120V/60Hz US-type NST, I ran it with 240V/50Hz UK mains current using a 2:1 step down transformer to reduce the voltage. The 50Hz current didn't hurt it a bit. At the moment I'm using it to power a small
Jacob's Ladder.