Whats the minimum and maximum king size for a tournament usable chess set.
Just curious. (I know, I really need to buy the rules book) 
I was also wondering, from a historical standpoint, what the “club sized” chess set? I vaguely remember reading someplace that a 4.4" king was club size. (When I mean historical, I mean going back 100 to 150 years.)
Obviously, nowadays, it would be too expensive to buy a chess set that big, not to mention rather unweilder to lug around to a chess club. 
From the USCF Rulebook
40B. Size.
The king’s height should be 3⅜ to 4½ inches (8.65 to 11.54 cm). The cross (or other King’s finial) should occupy no more than 20 percent of the total height of the King. The diameter of the king’s base should be 40–50 percent of the height. The other pieces should be proportionate in height and form. All pieces should be well balanced for stability and comfortable moving.
I actually bought one in '07, but ended up giving it away as a birthday present to a friend’s grandson. 
Since I don’t really have much opportunity to play in tournaments, buying the rulebook ends up being: “I’ll get one someday”… 
I’ve actually bought at least three 5th edition rulebooks.
Still don’t know what happened to the first - either lost it in moving, or I might have given it to the library during a move where I had to lighten my load. (And that was when the library would take donated books and put them into circulation if at all possible…)
Bought the second one, moved it around and then couldn’t find it when I first became a TD. Thought I might have lost it, so I ordered another.
Then I found the second one underneath the couch. 
But I had already marked up the third one. So I donated the second one to the local club.