Magpul Magpul MBUS Gen2 Rear Sight The MBUS (Magpul Back-Up Sight) is a low-cost, color injection molded, folding back-up sight. The dual aperture MBUS Rear Sight is adjustable for windage and fits most 1913 Picatinny rail equipped... MSRP: Was: Now: $57.95 Choose Options
