E Leitz Wetzlar Okularschrauben Mikrometer eyepiece

Description

I believe this is an old microscope attachment.
Lenses need to be cleaned, but appear to be scratch free.  Some tarnishing on the metal knob.
There are no model numbers or other markings that I can see.
There is a crosshair marking in the glass and the knob moves freely, but I cannot guarantee the functionality of this piece.
Sold as is.  Ask any questions before bidding.