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There are 3 insulator styles embossed with F.M.LOCKE that have any type of wire groove and any number of petticoats, shown below.

PLEASE NOTE: Insulators embossed with "F.M.LOCKE" were also manufactured by other glass companies, not just Hemingray. This database will only show the styles that were manufactured by Hemingray. Some insulator styles shown below may have been produced by other glass companies as well.

CD 204
CD 204
CD 287.1
CD 287.1
CD 287.2
CD 287.2