Nikon DW-4 6x Focusing Finder  type_Accessories A click-stopped mechanism allows the

A click-stopped mechanism allows the mount to rotate 90 degrees

and there's a separate

The Zeiss Makro Planar 50mm f2 T* for Nikon F is a full frame macro lens

These have pretty good compatibility

This FM3a is in good working order

Nikon DW-4 6x Focusing Finder &nbsptype_Accessories A click-stopped mechanism allows theNikon DW 4 6x Focusing Finder for the Nikon F3. This finder offers a magnified viewfinder image that is vertically corrected and laterally reversed. Great for macro work, astro, and any other application which requires focus precision. In excellent condition. Eyecup is not included, but the original box is!