A non-collector friend reminded me to mention these are limited production ornate glass pieces made one time only exclusively for industrial service in the power or communication industry almost a century ago. Most went to the landfills as lines were wrecked, replaced, or upgraded. As a result, glass insulators are as rare and sometimes as valuable as old precious metal coins.

(Just 7 drips with damage, and a shallow flake off the inside of wire groove.)

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