I do survey work, our measurements are by the foot, but in 10ths only. So, no 12 inches in a foot, there are 10 units of measurement per foot instead. We also use degrees, minutes and seconds for direction, sounds universal.
It’s not that hard to pick up, just like metric wouldn’t be difficult to learn if you do it enough. We learned metric in school, the rumor was the US would switch, nope, stuck in the past, oh well.
Grandpa left me the biggest box of tools, could be half the size, but no. Like he said, catch as catch can. Try this, which is the next size smaller from a 19/32, verses the next size down from a 10mm?