The Magpul MBUS 3 rear sight combines the best of both worlds from Magpul's line of back up sights. The low profile and minimalist design from the MBUS Pro combined with the lightweight impact resistant polymer of the original MBUS sights give you a cost effective and feature packed solution for mounting flip up sights on your rifle. When folded, the MBUS 3 sight is only .44" high and only 1.15" wide, so it sits on slimmer rails without overhanging. Additionally, the Magpul MBUS 3 rear sight features the same spring-loaded technology that can be deployed by the press of an ambidextrous button.Features: Polymer construction Spring loaded with ambidextrous button .44" high when folded 1.15" wide Standard AR height when deployed Dual apertures Toolless windage adjustment Made in the U.S.A.