This is an Arduino LPG gas sensor. It has MQ5 probe which is very sensitive with LPG, natural gas , town gas. It is less sensitive with alcohol, cooking fumes and cigarette smoke.
To ease the difficulty of using this sensor, a Gravity Interface is adapted to allow plug&play. The Arduino IO expansion shield is the best match for this senor connecting to your Arduino.
Interface type: Analog
Pin Definition: 1-Output 2-GND 3-VCC
High sensitivity to LPG, natural gas, town gas
Small sensitivity to alcohol, smoke
Stable and long life
Simple drive circuit