Magpul MBUS Flip-Up Backup Sights, Black, Rear Sight
The MBUS (Magpul Back-Up Sight) is a low-cost, color injection molded, folding back-up sight. The MBUS Front Sight is adjustable for elevation and the dual aperture MBUS Rear Sight is adjustable for windage. Fits most 1913 Picatinny rails. Made in the USA.