Zeiss Plan Achromat 40X microscope objective that fits the Zeiss Standard, Universal, Photomic, and Ultraphot microscopes.  It will also work with other 160mm TL microscopes from Leitz, Olympus, Nikon and others.  This objective has an N.A. of 0.65 and requires the use of a coverslip of thickness of 0.17mm.  It is in nice optical, cosmetic and mechanical condition; however, the case shows some small signs of wear.  There are no element separations.  Glass surfaces are free from fungus, dust, and scratches.