Collectibles--General (Modern)/Gayner insulator


I have just acquired what I think is an "open screw" Gayner insulator marked No. 48-400 and under that, a small number 7.  I have several Gayners and Lynchburgs but have never seen one that is open at the top with screw threads inside.  Is this a rare piece?  What was its use?  Thank you for your time.

Thanks for your question -- The Gayner insulators marked 48-400 are a telephone style with threads but not a through hole.  Look carefully at your insulator to make sure the top is not cleanly broken out, sometimes it appears to be a through threaded piece, but the top really has been popped off due to freezing, and it can be pretty clean.  Please attach a picture of your insulator so I can confirm.


Collectibles--General (Modern)

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Bob Berry


Questions related to collecting Glass Insulators and porcelain insulators - I can provide historical information as well as current collector values. I am also interested in purchasing insulators I need for my collection.


I have collected since the early 1970's and have much historical information, as well as knowledge of current insulator values.

National Insulator Association (

BS & MS in Electrical Engineering

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