New Nikon High-eyepoint YS 15X eyepieces for the Nikon Alphaphot series of microscopes. They have a field of view (FOV) of 12 mm. The barrel diameter is 23.2mm.  These eyepieces are new and perfect in every respect with all glass surfaces free from dust, scratches, element separation and fungus.  They are still in their original factory packing.  They can also be used on other microscopes with an eyetube diameter of 23.2mm.  The new Nikon part number is MCK50150 and old number 90412.