My Weston has 3.5 on the dial; maybe they courted Rolleiflex users.
I have a Graflex 22 -- a TLR with a Graftar 85mm/f3.5 taking lens. Made after Graflex bought out Ciroflex, I believe. So its f/stops go f3.5, 4, 5.6, etc...while an old Rolleiflex of mine goes straight from 3.5 to 5.6. No f4 marked.
Vaughn
At least with LF landscape, a bad day of photography can be a good day of exercise.