Hex Head Bolt tool sizes

And when the Whitworth system was replaced with the British thread sizes, tool manufacturers went to the modern wrench sizes. All these early wrenches are marked 1/2 AF or 3/4 AF or whatever. This means “across the flats” and indicates the marked wrench size is the actual opening, not the previous bolt size.

All the wrenches for my TR3 are AF wrenches.

Dennis

Who him ?

Any relation to Sir Joseph Whitworth, the renowned English engineer ?

Am I the only guy who just puts the socket any damn place into the case, and then has to repeat the whole process next time? They’re all marked, why can’t I take the time to put them into the right slot?

Probably because you, like me, once bought a set with good hardware and a shitty case, and after you spent the time to put them all into the correct slot, an accidental drop of a billionth of an inch(metric:bizilometer) cause them all to pop out and end up a pile the next time anyway.

Oops. Yes, that would be Joseph Whitworth.
Sorry