I have the usual metric and US open and Weatherhead, but on top of that some really large ones from an inch up to 3 or so. Actually use the big ones a fair bit (inside of power transformers when there is no room to swing a wrench on bushing jamb nuts. I will be making an even larger one later this month - once more for a bushing nut that is too close to others, core and wall to be able to turn a long (and very thin) flat wrench (laser cut from plate, 1/2 drive square end cut from an impact socket and welded on).