Ridge Pin : A device that allows the mounting of a pin type insulator to a pole. The ridge pin is bolted to the top of the pole and the insulator is screwed onto the threads at its top
Young & Company Electric Power Products and Related Engineering Services, Glossary of Electrical Terms, http://www.youngco.com/young2.asp?ID=4&Type=3, CA., USA 2001. (Electr Sfty - Amer) {514}