Solar water heater with Solar Keymark,CE,SRCC Solar thermal system High quakeproof, anti-hail ability 15years lifetime OEM ... which eliminate boiler scale prompt4) With the electric heater system ,guaranteeing the water can be used as normal in rainy day.5 ... , and installs very easily.6) With the electricity tropics,the water tank does not ice up. High Quality Compact Non-pressure Solar Water Heater