vintage red glass lenses for early automotive, railroad or traffic safety lights

Red glass lenses for old safety lights, traffic lights, railroad lights, or truck, tractor or car lights. They're early to mid-century vintage, I believe. But aside from that, I'm not sure what sort of lights they fit! (If you do, please let us know.)

These are 8" lights (8 1/4" edge to edge diameter) marked with a K - Kopp lights? Both are worn, with scratching and small chips to the rims.