1,Shell is stainless steel 304 or 316L 2,Can stand higher water pressure 3,Suitable for high temperature heat pump,spa ... water,ground water,sea water,and another corrosive solution.Material:1)Heat transfer Tube: Pure titanium seamless tube,Thickness 0.55mm2)Shell: stainless steel ... or 316L, So,it can used for high temperature solution,(stainless steel shell can stand 120 degree Celsiusthe , But the PVC ...