Originally Posted by
70sSanO
Like others, when I'm doing any sort of mechanical work I use both. But this would swing between when I was a kid, foreign cars, classic American cars, around the house, or bikes. There was a era when US cars used both. What a pain.
Then there were those old British cars which used Whitworth fasteners.... I am sure there are plenty of old-time mechanics who still have a set of Whitworth tools, gathering dust somewhere on a shelf.