... in all climates 3) Reliable and efficient with twin-glass solar tubes 4) Copper heat ... easily replaced if broken, can be used with broken tubes 14) Ideal for commercial solar water ... windowsAdvantages:1.CE,UL,ISO9001,CCC,Solar water heater with SOLAR KEY MARK certificate2.High efficiency, Absorption rate ... 3.Competitive price, all the parts are made by our factory. With the same quality of products, we ...