Rob H. wrote:
....

I sent this photo to an insulator collector, he had all different types
of them on his site but he had never seen this one before, so either
it's a rare insulator or maybe it's something else.
....

Well, are they hollow and are the ends actually removable? I thought it
was just reflection/refraction, but the second picture makes me think
the laboratory vacuum manifold of another respondent would quite
possibly be a good call if so...

They really aren't well-shaped for the purpose of an insulator as I look
again as well as it would be unusual for there to not be additional
support. I'm thinking I jumped to conclusion too quickly...

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