I picked up some Halex steel EMT set screw connectors.
I decided I would see if I could find some stainless hex screws for them, thinking that is an easy thing. After 15 minutes at Ace Hardware we figured out these use a M5-1.0 thread which seems not to actually exist anywhere (web search came bank no joy too).
What was wrong with the good old 8-32/10-32 or even a M5-.80?

Greg Fretwell