Quick Nautic Boiler BK. It manufactured by high quality materials and with Argon shielding gas and hence highly resistant to corrosive agents. Heat exchanger has wide exchange surface and fitted with an adjustable safety thermostat. Relief / non-return valve that allows discharging of the water heater in case of disuse. Outputs diameter is 3/4″. The thermal insulation is high thickness polyurethane foam injected between the cover and tank giving excellent heat retention properties.