In some areas there are still a lot of horizontally mounted 3"-4" E condulets with 3-hole nonmetallic covers for service-entrance risers. With the condulet opening pointed down, I think they're intended for outdoor use. And no ‘slip fit’ allowed—the raceways had to be threaded.
Also, there are a lot of older outdoor signs in service with outdoor-rated toggle-switch disconnects mounted in C-condulet covers. These days, tight dimensions and lack of attachment means in conduit bodies do not allow for wiring devices and terminations, but they have in decades past.
