Features , ED glass (extra-low dispersion fluorite) , 18-38X eyepiece w/ twist-up eye cup , BaK-4 prism glass , Emerald Fire™ full multi-coating , Multi-step eye relief system (eyeglass compatible) , Waterproof and fogproof , Nitrogen filled , Alloy frame w/ ergonomic body armor , Sight alignment tube , Tripod/monopod compatible , Extendable sunshade , Limited lifetiem warranty