The DRS1X lives up to its namesake with rapid and lethal target engagement at close quarters. The DRS (Defendu Reflex Sight) is so versatile and effective at close range, we&';ve named it after the famed Lt. Colonel William Ewart Fairbairn whose Close Quarters Combat system was designed to rapidly disable an opponent with potentially lethal force. Perfect for tactical operations or home defense, the 1x reflex sight offers three reticles calibrated for speed and accuracy at 7, 25 and 50 yards. The ultimate CQB sight, it is built with Steiner&';s legendary ruggedness. Lightweight, compact and simple to use. Included Accessories: Battery, Lens Cloth, Lens Cover PRODUCT FEATURES: Window size is .96 x 1.26 in. (height x width). The overall height is 2.57 in., and it sites 2.35 in. above the rail. RUGGED MAGNESIUM BODY CHOOSE FROM 3 RETICLE OPTIONS a single dot dot and stadia lines dot, stadie lines and close dot SEVEN ILLUMINATION LEVELS (4 DAY/3 NIGHT) ADJUSTABLE FOR WINDAGE/ ELEVATION WATERPROOF/FOGPROOF/ SHOCKPROOF POWERED BY TWO (2) AA BATTERIES, BUT CAN OPERATE ON ONE 2000+ HOURS OF BATTERY RUN TIME 13-HOUR AUTO SHUTOFF CO-WITNESS WITH IRON SIGHTS OR USE WITH ANY MULTIPLIER