Cute as a button - and these are definitely cute. They have a metal shank with a 2 mm hole - and fit nicely onto the 2 mm leather, if you were so inclined. Or you could make a toggle closure for a bracelet by beading a loop, or use in other buttony ways. And the cup in the middle - would be perfect for gluing in a rhinestone - and would take one any size from ss 20 to ss 29. (4.5 - 6 mm)
14mm Hole size is approx. 2mm. By the each.