most if not all of the SDG&E M250As have reverse sockets. i guess i didnt know ge used it that early in small fixtures. this is 100w HPS on a 120v line.
The M-250R FCOs had the street side sockets too and the detailed reflector. They probably started doing that in the very late 70s since the M-250R FCO in my 1977 catalog has the smooth reflector with the house side socket.
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