... direct MQ-2 smoke gas sensor module methane liquefied flammable gas for Ardu Product DescriptionMQ-2 gas sensor using gas-sensitive materials with ... monitoring means, suitable for liquefied petroleum gas, butane, propane, methane, smoke, etc., the probe can be used in homes ... The wiring diagram of the sensor module New Factory direct MQ-2 smoke gas sensor module methane liquefied flammable gas for Ardu ...