I’ve seen many old GE fluorescent starters and ballasts with Spec NO. 6 marked on them. What was this specification? Was it a standard before the ANSI standards for fluorescent lamps, ballasts and starters came into existence? Also, I presume it dated from the era when GE had a practical monopoly on light bulbs in the U.S, before they lost the antitrust suits against them to the Department of Justice in the 1940’s.