HD Glass HD Glass gives you better light transmission,brighter, andsharper image. Illuminated Reticle The illuminated reticle provides greater visibility during dusk and dawn and other low ambient light environment. Etched Glass Reticle Reticle etched on the glass that provides excellent backing support for complex reticle design and offers great durability and much higher shock resistance to recoil Advanced Fully Multicoated Fully Multicoated optics effectively reduces reflected light and increases the transmission of light giving you a brighter image than normal single coated lenses XPL Coating XPL Coating gives you an extra protection on the exterior lenses from dirt, oil and scratches or anything else mother nature can throw at you. Precision Zero Stop System The system allows you to lock down your zero position and dial back to it with a sharp and precise stop right at your zero mark even you are turning it in pitch-dark or blinded folded. High Precision Erector System The high precision erector system processed by high precision CNC machine with +/- 0.0001mm tolerance level to provide you the mostaccurate power settings and smoothest magnification change 6061 T6 Aluminum The 6061T6 aircraft grade aluminum tube that has exceptional strength and superior mechanical integrity will protect these world class optics no matter what punishment you throw at it. Heat Treated One Piece Tube Construction Heat treated one piece tube gives the scope extra strength over multi-piece tubes.A one piece tube also is better at keeping moisture out thus keeping your scope fog proof for the life of the product Waterproof Waterproof to protect the scope in the harshest weather conditions or if accidently submerged underwater Fog proof Fog proof to allow you to immediately engage your target when you take your rifle to cold ambient temperaturefrom warm inside Shockproof Robust mechanical system with special designs on both control and erector system that give you the ultimate recoil resistance to withstand 1000G recoil for 1000 times. Argon Purged Argon Purging uses the inertia gas with bigger size molecules to purge any moisture out ofthe tube giving you better waterproofing and thermal stability.