General Electric M400 "split door"

An early HPS example of the M400 split door series, which came out in 1970-1971. This example is from 1976. 400w S51 lamp. Fixture is not mine.

[@ALT-9167]

My state used M400As exclusively on freeways and major arterial streets. Before the 90's though, they were mercury vapor. They were also the early versions that had the 2 slots at the sides of the GE monogram.