Alot of stuff is reffered to in inches over here. But it is slowly changing to our standard metric system. Nails are often said as 3",4" and so on while it's labeled as 75mm, 100mm and so on. Timber is also the same, we say 2x4 and 2x6 while it's sold as 50x100 and 50x150. But it's true like you say. The ratchets and sockets are still only measured in inches here. Strange indeed.