Pin-type electrical insulator, ca. 1897Item 74827 info
Maine Historical Society
This insulator, a type made in late 1896 and early 1897 by the Imperial Porcelain Works of Trenton, New Jersey, was used in the Sanford area.
It was an early porcelain insulator and proved so popular that the plant could not keep up with the demand and quality suffered.
By the 20th century, however, porcelain replaced glass as the most common insulator material.