Nikon visor cap, usefull to take long exposures or take dark frames or biass for astrophotography and prevent light enter through eyepiece.

Works on my nikon D40 and D7200. I have not tested in other cameras, but probably it should work.

External dimensions of my D40 and D7200 eyepiece are 24.9x15.8 mm.

Print in black filament.

Print vertical and you won't need supports.