Nikon F Stereo Nikkor prototype *

Most probably a unique stereo Nikkor lens 3.5/35mm (?) prototype for Nikon F, the barrel design similar to the 2.8/45mm GN Auto, but with infinity focus to the left, serial number engraved on the rear, automatic aperture for both lenses, it might be the only existing example, especially knowing Nikon’s policy to destroy any prototypes they have made so they couldn’t end up in a competitor’s hands and taken apart to be studied, with very rare original NKJ blue rear cap - known from the other existing prototypes