Is it a bushing? Is it a spool?
We don't know for sure, but so far the general consensus is this piece is likely a bushing, so it's being filed here until we find out more.
What we do know is, in 2008, one of these was dug out of the Hemingray Dump by Roger Lucas (photo here). It's a rather unusual insulator, and almost resembles a stretched version of CD 1074.
It has a tapered bore like the wall tubes shown above, but it also has what could potentially be a wire groove. The measurements are 4 1/4" high, 2 1/4" wide at the middle, with a tapered inner diameter of 1 1/4" at the top to 1" at the bottom.
It comes in a typical Hemingray ice aqua color, and there are at least three specimens known to date. It has never appeared in any Hemingray catalogs (that I know of). Does anyone else out there have one or know more info about this piece? Contact me!