4-in-1 Upgraded Detector: The upgraded 4-in-1 Natural Gas Leak Detector & Carbon Monoxide Detector is equipped with natural gas, carbon monoxide, temperature, and humidity detectors, powerful functionality, dual sensors, a dual alarm system, and quick response to protect your ...4-in-1 Upgraded Detector: The upgraded 4-in-1 Natural Gas Leak Detector & Carbon Monoxide Detector is equipped with natural gas, carbon monoxide, temperature, and humidity detectors, powerful functionality, dual sensors, a dual alarm system, and quick response to protect your family and personal safety in all directions. It supports carbon monoxide, methane, LPG, LNG, Fuel, natural gas, propane, fuel, ethane, butane, alcohol, coal gas, gasoline, toluene, kerosene, sewer gas, and other flammable gases. MODERN WALLS LLC