... protection *Food-grade stainless steel solar water heater tank /pressurized water tank with coil/water tank *CE, ISO9001, ISO14001*Energy-saving and environmental protection ... steel MaterialInner tank: food-grade SUS304/2B Outer tank: Galvanized alloy , soft coverInsulation: Polyurthane Coil: Copper , Stainless SteelThicknessInner tank: 1.5,2mmOuter tank: 0.5mm ...