The Classic Army Flip Up Rear Sight for M4/M16 is a great way to modify the looks of your M4/M16 to make it stand out from the rest. This sight has functional flip up/down, nighttime and daytime aperture settings, as well as functional windage adjustments. Flip sights are great for use with guns that have attached optics so they can be flipped out of the way to make aiming quick and easy.
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