The M-Tactical Scope Series is the result of Nikon’s effort to make a tactical riflescope using the best possible optical glass, highest quality materials, and innovative riflescope design. M-Tactical scopes are available in three magnifications: 1-4x, 3-12x, and 4-16x. The optical glass used in M-Tactical Series riflescopes is fully multicoated for superior clarity, contrast, and brightness. Additionally the reticles in these scopes are designed for platform focused ballistics. M-Tactical Series riflescopes four reticle types: MK1-MOA, MK1-MRAD, BDC 600 (for .223/5.56x45mm) and BDC 800 (for .308/7.62x51mm). The long range focused Nikon M-Tactical models feature Side Focus Parallax Adjustments that allow you to make corrections without compromising your shooting position. Features of the Nikon M-Tactical Series Riflescopes Rugged 30mm Main Tube is constructed from aircraft grade aluminum Quick Eye Focus allows for quick target acquisition and reticle focus Directional Indicators allow for quick adjustments Spring Load Instant Zero Reset allows you to quickly return to your determined zero 4x Zoom is ideal for versatility at allow ranges Waterproof and Shockproof ensures a long service life Nitrogen Purged to prevent fogging due to temperature shock Nikon M-TACTICAL Riflescope .308 4-16X42SF Matte BDC800 16517