solar power water heater 1.CE mark 2.Adjustable frame,easy and safe to use and protects freezing 3.Good quality solar power water heater1.Outer water tank:non-corrodible colored steel,0.4mm thickness 2.Inner water tank: SUS304-2B stainless steel(food class),0.4mm thickness 3.Vacuum tube:high quality borosilicate glass,AL-N-AL coating,1.5mm thickness4.Heat Preservation:Polyurethane Foam,50mm ...