The MQ4 is used in gas leakage detecting equipment in consumer and industry markets, this sensor is suitable for detecting CH4, Natural gas, LNG, avoid exposure to alcohol, cooking fumes, and cigarette smoke. The sensitivity can be adjusted by the potentiometer.
Power supply: 5V
Interface type: Analog
Pin Definition: 1-Output 2-GND 3-VCC
High sensitivity to CH4，Natural gas
Small sensitivity to alcohol, smoke
Stable and long life
Simple drive circuit
This product and description is from DFRobot.