Specification
Arduino compatible gas sensor
Detects smoke, methane, carbon dioxide and other gases
Gives alarms when the smoke/gas leaks
Power supply needs: typically 5V 
Pin Definition: Output,GND,PWR

The Gas Sensor is capable of detecting various gases, for smoke, methane, carbon dioxide and other gases.
This arduino compatible special sensor raise alarms when the smoke, methane or any other harmful gas leaks in its reach. 

Arduino Test Code:

void setup()
{
       Serial.begin(9600);
}
void loop()
{
       int val;
       val=analogRead(0);
       Serial.println(val,DEC);
       delay(100);
}