The Sig Sauer® ROMEO5® 1x20mm Compact Red Dot Sight is a state-of-the-art tactical optic system, designed to deliver quick, intuitive target acquisition with most rail-equipped long guns. The ROMEO5 features high-performance lens coatings for excellent light transmission, color fidelity, and contrast in any environment. The 2 MOA illuminated red dot reticle offers lightning-fast target acquisition, while 10 user-selectable brightness settings (8 daylight; 2 night vision) ensure reliable clarity in virtually any lighting. Built-in MOTAC™ (Motion Activated Illumination System) technology automatically activates the red dot when it senses motion, and powers down when the weapon is idle for an extended period of time, delivering an impressive 40,000-hour battery life on a single CR2032 battery (included). The shockproof, CNC-machined 6061 aircraft aluminum housing delivers lasting durability and superior corrosion resistance and comes ready to mount to standard Picatinny rail systems. IPX7 waterproof and fogproof.