MQ-135 Module (Ammonia, Sulphide and Benzene Gas Sensor)

Specifications: Wide detecting scope Fast response and High sensitivity Stable and long life Operating Voltage is 5V Detect/Measure NH3, NOx, alcohol, Benzene, smoke, CO2, etc. Analog output voltage: 0V to 5V Digital output voltage: 0V or 5V (TTL Logic) Preheat duration 20 seconds Can be used as a Digital or analog sensor The Sensitivity of Digital pin can be varied using the potentiometer