... 2.ISO,CCC,CE 3.high efficient,heat quickly,72 hours for hot water 4.5 years warranty Techinical ... stainless steel or color steel 3.Absorbing layer: high-pressure polyurethane foam with 55mm thickness 4.foaming density ... on the inclined and flat roof2. supply the hot water in 72 hours3. wind-resistance,snow resistance for 15 ... tubes5. energy-saving, efficient, heat quickly. house solar water heater