I has the incredible pleasure to hold and examine both of these rare jewels at this years national up close. The CD 178.5 is an insulator designed by Fred M Locke around 1915 that used one of his experimental glass formulas. . Only two or three examples of this CD are known to exist and both of them showed up at the national. We were very lucky to get both together for a photo shoot for the very first time. The mold for this insulator has the characteristics of late Brookfield but the glass looks more like Fry glass. Both pieces were clearly made in the same mold. One was made before the FM Locke embossing was engraved into the mold and one after. Both pieces were made from the same experimental glass formula that gives the insulators a unique lemon opalescent color. I suspect these are the only two examples of this CD that still exist. since I am a big Fred M.Locke fan this was a really unique opportunity to view these up close and personal. See less