It was suggested the bottom shells of this insulator were that of New Lexington M-3890. They are almost identical; but the new insulator is by far taller and the shells are less flared. The shells are very thin and fragile. It seems this particular design was an ill-fated attempt at improving the M-3890 concept by adding a forth shell to improve puncture resistance. This insulator looks like a bigger version of the ridiculous Thomas M-3990. What really makes me wonder is why the glaze color is identical to the M-3890... were they available at the same time? The mill these were recovered from was in New York state and the building they were in appeared to be a transformer house (there were no transformers in it). Unfortunately the only way I could get these answers is with a time machine.

Being inside a building for the past 100+ years and the several inches of bird poop covering them was the only reason these things survived. I will be posting pictures of the top here in the future.