Jasen Betts wrote in a message to Roy J. Tellason:

 RJT>> followed by "ZNR",  which leads me to believe that this is 
 RJT>> perhaps a MOV.  Under that it says "10K24IU" or
"10K241U".
 RJT>> There's some more stuff below that that I can't make out..

 RJT>> Anybody know what this is?

 JB>> sounds like a 240V MOV, could that be?  if so it'll be fatter
 JB>> than your average disc capacitor.

 RJT> I don't know why I'd have one with that rating,  maybe the number
 RJT> refers to something else

 RJT> Since you bring up the dimensions,  it's a bit under half an inch
 RJT> in diameter, a bit over an eighth of an inch thick.  Black in
 RJT> color,  looks like the package was made by "dipping" whatever it
 RJT> is into the packaging material.  Shiny, though,  not dull like a
 RJT> ceramic cap would be

 JB> I've got a cataloguue with a picture of some MOVs. these ones are
 JB> blue, shiny, and have the tiangle (with smaller triangles at the
 JB> corners) logo and some writing that isn't printed clearly.

 JB> possibly it was for telephone applications?

Possible,  but I don't think so.  The sort of hardware this thing is using
for connection points leads me to believe it was handling line power...

Does that catalog mention who that logo belongs to?  Maybe I oughta try a
web search on either "ZNR" or that part number...

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