The ROMEO-RS (Reinforced Steel) was specifically engineered to provide the accuracy and convenience of a pistol-mounted red dot at a cost that competes with high-end iron sights. Inspired by the design of modern striker-fired pistols that employ high-strength polymer and metal, the ROMEO-RS housing forms around a rugged steel chassis that supports and protects a premium aspherical glass lens. Metal inserts allow for optimal torque load when mounting the optic to a pistol slide and installing the side-load battery tray, while additional metal inserts provide increased accuracy and long term durability for the windage and elevation adjustment mechanisms. The ROMEO-RS features a convenient side-mounted illumination adjustment button embedded into the polymer housing to prevent accidental interference, and the side-load battery tray makes battery replacements easy to do while maintaining zero. SIG SAUERs updated footprint design maintains true compatibility with industry-standard optics cuts while allowing for the additional lock-up strength provided by steel recoil pins to eliminate the potential for any lateral shift. Built in Tualatin, Oregon, the ROMEO-RS was engineered to deliver premium red dot functionality at a cost thats within reach of any shooter. Specifications for SIG SAUER Romeo-RS Pro 1x31mm Reflex Red Dot Sight: Manufacturer: SIG SAUER Magnification: 1 x Objective Lens Diameter: 31 mm Reticle: Red Dot Optical Coating: Spectracoat Battery Type: CR1632 Length: 1.83 in Weight: 26.6 oz W/E Travel at 100 Yds: 70 MOA Features of SIG SAUER Romeo-RS Pro 1x31mm Reflex Red Dot Sight Hybrid design featuring a skeletonized steel chassis, molded into a high-strength polymer housing Molded glass aspheric lens for a distortion-free sight picture High efficiency point source LED emitter with 8 individual brightness settings Large side control button for easy reticle adjustments Convenient side-mounted CR1632 battery tray with security screw for easy access without removing the optic from the firearm Minimum continuous runtime of 20,000 hours (at medium setting, dot-only) MOTAC (Motion Activated Illumination) that powers up when motion is detected, powering down when inactive Fully Backed by SIG SAUERs Infinite Guarantee Package Contents: SIG SAUER Romeo-RS Pro 1x31mm Reflex Red Dot Sight