TRUGLO Tru-Brite Xtreme 4-16X50 BDC IR Scope Black Ultra-high contrast, high resolution mechanical and optical design. 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 can be easily calibrated to most centerfire cartridges and accommodate targets up to 600 yards away. See-thru / flip-up lens caps, optical quality / all-weather. Rubber-coated, speed-focus eye-piece. Specially formulated multi-coatings provide maximum brightness, clarity and contrast even in the poorest of light conditions. Special internal anti-reflective coating on metal parts. Zoom index at 9 oclock for more ergonomic use. Low-profile, large diameter W/E adjustment drums. Durable leaf spring for windage and elevation adjustments. Adjustable rheostat for brightness control. One-piece tube made of aircraft quality aluminum. Durable, textured, non-reflective matte finish. 3V-CR2032 lithium battery. Lifetime Limited Warranty.