A 1918 Fox, of course, would have been made before the appearance of the Super Fox. A bit hard to tell from the photos in McIntosh's book, and while he stresses that the Supers were heavy guns, he doesn't mention that they all had overly thick wrists. They wouldn't look or feel right with a very thin wrist, but it would be interesting to measure some and compare to the above XE and RBL.