The Sig Sauer ROMEO8H Red-Dot Sight features a 38mm rectangular viewing window that provides a wide field of view with minimal obstruction by the housing. ROMEO8H is parallax-free with unlimited eye relief for rapid target acquisition with both eyes open and head up. The ROMEO8H model runs off 1 CR123A battery (included). MOTAC (Motion Activated Illumination System) automatically turns the unit on when it senses motion, and powers down when the weapon is idol. The 2-MOA red dot has 10 daytime illumination settings, and 2 night vision settings. You can also select from 4 different integrated reticle options (dot, circle/dot, dot with 3 holdover dots or circle/dot with holdover dots). Constructed with an aluminum housing and premium glass lenses. SPECTRACOAT anti-reflection lens coatings provide optimum clarity, and LENSARMOR lens coatings resist abrasion to ensure years of enhanced brightness. The ROMEO8H Red-Dot Sight is waterproof rated at IPX-7. The unit comes with a rugged hex-bolt mounting system that attaches the sight to any Picatinny rail. Includes flip-up lens covers. Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Red Dot Sights.