... tank:Galvanized steel,0.4mm,diamater of water tank:460mm 3.Insulation layer:50mm high dense integral polyurethane foam4.Bracket: ... ,1.2mm,1.5mm.Angle:20-50degree. 5.Vacuum tube: borosilicate glass 3.3 Three-target vacuum tube(58mm *1800mm). Hail resistance: 25mmsell pressurized ... Solar Keymark,SRCC,ISO9001 certificate.We offer 0.8% vacuum tubes for free for exchange in case several shattered vacuum ...