@ Michael, nope never internally ballasted, those were the VERY first GE MV fixture that used Medium Pressure Mercury Vapor, and later they got the regular 400 watt MV......those came out in 1948. Those were remote ballasted. The first GE fixture that was internally ballasted is the GE M-400.....although before that the first clamshell to be internally ballasted was the GE Form 400 Power Pack....This Form 109 was from BEFORE the Form 400.....Those I am not sure if it's considered a clamshell, but it was the first MV designed fixture for GE while for Westinghouse it was the OV-20 stamped version...
I sort of used to be an Illinoisian, specifically in Northbrook, Illinois....but only for school
I sort of used to be an Illinoisian, specifically in Northbrook, Illinois....but only for school