> Even in the U.S. of course, for engineers, mechanics, and some others they still have to deal with a mix. s/U.S./the entire world/ It's very common to have

> Even in the U.S. of course, for engineers, mechanics, and some others they still have to deal with a mix. s/U.S./the entire world/ It's very common to have international U.S. based companies offer N types of fasteners/whatever in imperial sizes, but only N/2 in metric. So we frequently build stuff in imperial sizes because of greater flexibility. And don't get me started on (non)tapered pipe threads... I've heard some horror stories of huge subassemblies built in Europe using BSPT and shipped to the U.S. for final assembly, where of course everything else is NPT, so some poor sod has to spend a month replacing all subassembly fittings.