... standard tube 3.High anti-corrosion tank 4.OEM available Home Use Compact Unpressure Solar water heater Shell: Adopt the imported new ... film coat adopts magnetron sputtering, optional film coating. Three target: copper, aluminum, stainless steel, multiple absorption, multi-heating, stronger power ... , time display, memory function in case of power off. Home Use Compact Unpressure Solar water heater