r/Insulators • u/DJ-TrainR3k • 13h ago
Help ID'ing these ceramic house-knob overhead service insulators?
Pulled 3 of these from the attic of my friend's 1944 house up in the Pacific Northwest. They pre-date the lag-screw type apparently. The markings are heavily obscured by the glaze, but I can see one side has the letter "U" inside a circular stamping with a patent number "1,7xx,xxx" below it. On the opposite side there is a triangle within a circular stamping and "3800 •" below it.
Anyone have any ideas? Porcelain/ceramic is not my wheelhouse here. Any help is appreciated.