Compact pressurized solar water heater 1)Best quality 2)anti-freeze:-50 degrees 3)high quality 4)long life-span compressurized solar water heater: Certificate:CE, CCC, ISO9001-2000, SRCC, SOLAR KEYMARK Specifications: Tank: 1) Inner tank: SUS304 -2B /SUS316food degree stainless steel, thickness: 1.2mm 2) Out tank: galvanized steel 3) Insulating layer: High density Polyurethane, 55 mm Vacuum tube: ...