[Well, maybe not all large format . . .]

In reviewing the (alas, largely unused) sheet film cameras in my possession, and trying to get the bigger picture, I ran into a question that google (within my skill) hasn't covered.

At least on Graflex cameras, was the Graflok just a 4x5 feature, or was it used on other (smaller) size cameras?

And, while I'm bothering people, is it also used on larger formats (not that I can afford that temptation)?