High quality design with brass valve body, valve stem, and cap assembly;Valves have additional safety feature of automatically closing if a high-temperature event exceeds the valve rating (165 Degree F or 200 Degree F);All washers and o-rings are made of Viton equivalent material;Robust handwheel design, improved in 2018. 165 Degree F or 200 Degree F closing temperature, depending on model;Approved for kerosene, ASTM D396 for No1 & No2 fuel oil, ASTM D396 for B6-B20, and ASTM D975 for diesel fuel