Eye cup rubber shows some wear, mostly around the upper rim. And it has some piece of rubber cut out. Please look at the pictures.  I don't know what camera brand it might fit. Maybe it is for scope? Or maybe for microscope eye piece?

Rubber eye piece does not have any threads. It is only rubber. It seems to be slip on type eye piece. It might be missing metal ring that would keep it on the finder. 

Eye cup will be mailed just as pictured, so please look at the pictures above.  I will pack it well to protect it from damage during transportation.

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