Powerful solar energy water heater. 1.For 15years warranty! 2.CE,CCC,ISO,,approved! 3.OEM is welcomed! 4.Sample offer Powerful solar energy water heater --------------------------------------------------------------------------------------Material and Features:Inner tank material:SUS304-2B stainless steel 0.4mm thickness,food grade,innocuity.Outer tank material:color steel 0.4mm thickness, ...