Lens fog is a performance killer so we developed a three-tiered defense. First we devised surge ports to control airflow. Second we formulated F-3 Series anti-fog treatment. Third we engineered a dual lens design to reduce fog with a thermal barrier of trapped air. Then we took all that technology and juiced it with the precision of HIGH DEFINITION OPTICS® (HDO®) topping it off with a wish list from the pros: 100% UV filtering impact protection that meets all ANSI Z87.1 / ASTM F659 standards durable urethane that stays flexible and comfortable triple-layer polar fleece foam with moisture wicking. About the only thing you don’t get with the A FRAME® goggle is fog.