STAEDTLER-Drawing any curve is possible with a set of French Curves! These clear curves are made of .080" (2 mm) thick plastic. They range in size from 6" to 10½". Beveled inking edges. Art Alternatives-A set of three of popular-sized French curves (5-1/2", 6-1/2" and 12-1/4") in a re-usable, divided plastic pouch. The curves have a smoke tint for easy visibility and double inking edges for smear-free ink work.