Collectibles--General (Modern)/Ceramic insulator


Brown ceramic insulator
Brown ceramic insulato  
I found a brown ceramic insulator and was curious about the value. After googling I discovered the logo, a "B" inside of an oval is the mark for Ohio Brass, but could not find info on my specific style. Any additional information would be appreciated!

Your insulator is made by Ohio Brass and I would date it to the 1925-1935 era.  They style is designed for telephone wire use and is called a transposition.  This was a special purpose insulator to allow telephone wire pairs to "cross over" every thousand feet or so to reduce crosstalk (like twisted pair wire).  Insulator collectors have developed a numbering system for these porcelain insulators called the "U number system".  Here is a link to some transposition styles: -- it is a little hard to tell from the angle of your picture, but I suspect yours is U-206.  These typically trade in the $8-$10 range so pretty nice pieces.  Hope this helps,  Thanks, --Bob  

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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