The MBUS (Magpul Back-Up Sight) Pro is a corrosion-resistant all-steel back-up sighting solution that delivers maximum functionality and strength with minimum bulk at a price that's even smaller than its size. Case-hardened and finished with Melonite QPQ for extreme resistance to wear and corrosion. The dual aperture, windage adjustable rear and no-tool, elevation adjustable front excel in all 1913 Picatinny rail mounting applications, including rail-height gas blocks. Positive detents keep the MBUS Pro Front and Rear at standard AR sight height when deployed, and so low when they are stowed that you'll never notice them until they're needed. Narrow width front sight is compatible with most IR aiming laser and light installations for the professional user. 1 MOA (1.131"/100m) per click with a 14.5" sight radius. 0.7 MOA (0.820"/100M0 per click with a 20" sight radius. All MBUS Pro Front Sights now come factory-equipped with the Enhanced Front Sight Post (MAG553). Made in the USA.