The Magpul MBUS Gen 2 Flip-Up Sights for the AR-15 continue the Magpul tradition of innovative and extremely high quality products. New features on the Gen 2 sights are a reduced size, greater optics compatibility and a spring-locking front sight post. The dual aperture MBUS Rear Sight is adjustable for windage and fits most 1913 Picatinny rail equipped weapons, but is specifically tailored to the AR15/M16 platform. Spring-loaded flip up sight easily activated from either side or by pressing the top. Protective wings shield the dual, same plane flip apertures. Sight can still be folded with either large or small aperture in position. Detent knob easily and positively adjusts windage.