... Solenoid valve, siren CO gas detectorProduct description:The combined detector works flammable gas detector, detect such as lpg, city gas, natural gas ... and carbon monoxide sensor. it can monitor the presence of flammable gas precisely, such as methane, propane, butane, hydrogen, ... of gas be detected: carbon monoxide, lpg, ng(lng), other flammable gas 9) Alarm sensitivity: co: 100± 50ppm gas: <10 ...