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Glass Spool and Knob Insulators

Spool or knob insulators typically have a non-threaded hole in the center for mounting and a wire groove around the outside.  These insulators are used for dead ending a communication or power line and are often found mounted on racks on the sides of buildings where the wires enter the building.  They are also used for wire transposition where two or four spools are mounted such that the wires can tie off and cross.  Glass spool and knob insulators have been assigned CD 1049-1110.  See the following reference for more information:

Insulators - A History & Guide - Price Guide - John & Carol McDougald

CD 1049

CD 1052

CD 1070

CD 1087

CD 1104

CD 1105

Peacock from Columbia


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