Some aircraft batteries terminals went over to metric for a while too.... I have the odd socket over 2 inches in diameter that came in my initial tool set and some 3/4 drive, never thought I'd ever need them, but have used them once or twice to get me and others out of the poo... So as said hang onto them. I also have metric in my box, a draw full of spanners etc, simply for those odd items that turn up and use them.
If you ever get onto Helicopters, the likes of Puma are all metric.
Last edited by NutLoose; 16th Dec 2012 at 10:29.