DOUBLE SOLENOID VALVE* For best in-class-safety. 99.9% PURE ELECTROLYTIC COPPER Heat exchanger to maximize heat efficiency water heate FULLY AUTOMATIC Hot water starts to flow when tap is turned on and stops when turned off. OXYGEN DEPLETION SENSOR Incase of oxygen depletion in the area, i it will automatically cut off the gas supply. FLAME FAILURE DEVICE Automatically cuts off the gas supply if flame goes out. CHILD SAFETY SWITCH Additional safety measure for under age children.