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There are 11 insulator styles embossed with H.G.CO. that have any type of wire groove and any number of petticoats, shown below.
CD 133
CD 133
CD 145
CD 145
CD 151
CD 151
CD 160
CD 160
CD 162
CD 162
CD 164
CD 164
CD 196
CD 196
CD 196.2
CD 196.2
CD 196.5
CD 196.5
CD 201
CD 201
CD 317.7
CD 317.7