US Patent 9683811 Low-profile folding sight with adjustable aperture

Disclosed is a low-profile folding sight assembly having a base configured to be secured to a gun and an arm mounted on the base for pivotal movement between at least a folded position and a deployed position. A first sighting aperture having a first size is provided adjacent a distal end of the arm. A selector member on the arm has a second sighting aperture of a second size and is slidably movable between at least a first position in which the first sighting aperture is unobstructed and a second position in which the second sighting aperture is aligned with the first sighting aperture to present a reduced-size sighting aperture.