... :more than 10years 4.Keep hot unpressurized water tank 1,Inner tank:SUS304-2B material,150L-200L1.2mm thickness,300L ... -400L1.5mm2,Insulation:50mm polyurethan foam3,Outer tank:0.5mm thickness galvanized steel material4,P/T relief ... Seals and rubber RingsHTV grade silicone rubberOptional installation angle38° stand (ground and flat roof installations)Maximum Operating Pressure12 bar ...