Porcelain Threadless Pintype Insulators from the United States

Note:  Click on each insulator for larger pictures and more information!

U-970 through U-990 are early threadless insulators for telegraph use

U-970 U-971 U-972 U-972A U-973 U-974 U-975 U-975A U-976 U-977

U-978 U-978A U-979 U-980 U-981 U-982 U-983 U-984

U-985 U-985A U-986 U-987 U-988 U-988A U-989 U-990

U-991 through U-999 are special styles

U-995

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