... Solar water heater with Solar Keymark,CE,SRCC Solar thermal system High quakeproof, anti-hail ability 15years lifetime OEM Inner tank material:SUS304-2B stainless steelInner tank ... boiler scale prompt4) With the electric heater system ,guaranteeing the water can be used as normal in ... .6) With the electricity tropics,the water tank does not ice up. High Quality Compact Non-pressure Solar Water Heater