Midwest Industries' Back Up Iron Sight (BUIS) has a simple, rugged design. Made from 6061 aluminum that is mil-spec hard coat anodized, it comes with a lifetime warranty. The sight's standard dual aperture is fully protected from accidental damage. A flush windage knob uses A1 style adjustment to provide 50 MOA for a rifle and .65 MOA for a carbine. An Allen wrench for installation is included. The USA-made BUIS retails for $79.95.