Dual-color illuminated reticle allows choice of red or green for faster target acquisition in low-light conditions. Reticle can be used in black without illumination. Waterproof / fog-proof / nitrogen gas-filled. BDC (Bullet-Drop Compensating) models have special reticles that can be easily calibrated to most centerfire cartridges and accommodate targets up to 600 yards away. Shock-resistant to 1000g. See-thru / flip-up lens caps, optical-quality / all-weather. Rubber-coated, speed-focus eye-piece. Easy zero-in. Specially formulated multi-coatings provide maximum brightness, clarity and contrast even in the poorest of light conditions. Zoom index at 9 o'clock for more ergonomic use. Low-profile, large diameter W/E adjustment drums. Durable coil spring for windage and elevation adjustments. Rheostat with adjustable brightness intensity. One-piece tube made of aircraft quality aluminum. Durable, scratch-resistant, non-reflective matte finish. CR2032 lithium battery. Lifetime Limited Warranty.