At least with all these standards they are in English, the Japanese have to contend with "1/4" Whitworth" in their camera manufacturing industry.
John
Think you will find they have been 1/4 UNC for years
Steve
.
Quite true, Steve
and, as discussed on this forum several times before; the specified 'fit' is sufficiently loose to make it "compatible" with 1/4" Whitworth. … Such is 'progress'