Here's a hard to find glass disc shaped insulator that was used to insulate cables through substation walls. Lightly embossed "ESPERANZA S.A. 121 -E.V." Measures 5.25 inches across.

Excellent condition with no chips or cracks. Scuff marks inside hole and a few teeny rim nicks from usage. Lots of cold mold pour straw lines on reverse. First email gets this tough insulator for only $45 plus shipping. Thanks