... food grade stainless steel inner tank 3. High density import polyurethane. Separated Storage Water Tank---Pressurized TankCE,SRCC,ISO,SGS passedWATER ... plateInner tankSUS 304-2B food grade stainless steelInsulation layerHigh density polyurethane foamHEAT EXCHANGER MaterialCopper coilSizeDia. 12mm, Thickness1.0mm Copper coil numberNone ...