Here's a rare unlisted porcelain slot-top insulator with an eye hole, stamped in green ink "SIMPLEX" (skirt) and dome stamped "D.C.T. N.1". This is likely an abbreviation for Department of Communication and Telegraphs. Brazil used 3 standardized styles (as did most nations) during this era. Measures 5" tall x 4 inches wide. Made in Netherlands and exported to Brazil circa 1900.

This company made the famous ceramic wire nuts that collectors have pondered for years. The same company made this unusual insulator based on a circa 1880 Capanema Patent, which allows the insulator to house the telegraph wire in its slot without the need for a tie wire! The hole was available to put a single pin through both sides and be soldered to the wire in the event the telegraph line would be rarely accessible or maintained which would extend its longevity and prevent flashovers. In this example the dome tapers inward from the top. The capanema example the head tapers outward at the top and the slot is V shaped.

This rare insulator is not found in any of the books or the NIA website and is in factory Mint condition except for a few tiny stains and a partial pin cemented in the pinhole.

First email gets this rare unlisted insulator for only $550 shipped. Only one known by seller. Thanks!