Revesun 1 Pack LPG Natural Gas Leak Senson Detector Alarm MCU Processing Adopted, Auto Detect Sensor Fature, High reliability dual sensor design, SMT control, High Stability Warning Alarm Wired Combustible Gas Detector Sensor for detecting leaking of gas, natural gas, liquefied petroleum gas Can be used individual , or used with solenoid valve or manipulator system Alarm output : sound ( 70dB/m )and LED flashing indicator ( red light ) , Automatic reset after alarm LPG natural gas leak senson detector alarm