... module methane liquefied flammable gas for Ardu Product DescriptionMQ-2 gas sensor using gas-sensitive materials with lower conductivity ... gas concentration using a simple circuit.MQ-2 gas sensor for liquefied petroleum gas, propane, high sensitivity of hydrogen, natural gas ... leak monitoring means, suitable for liquefied petroleum gas, butane, propane, methane, smoke, etc., the probe can be used in ...