?Military Standard Verification -AMAZTIM C20 PRO features the combination of 1.72" Corning Gorilla Glass screen enclosed by space aluminum alloy metal, making it the toughest and sturdiest watch. Successfully passed 12 (Twelve Military Tests) Including, extreme temperature, lowest pressure altitude, dust resistance, salt spray, fluid pollution. Certified to MIL-STD810H , our smart watches for men ensures that you use them confidently in a variety of harsh conditions. No matter how tough and hard the environment is, our rugged smartwatch is going to be your ongoing reliable companion.