HABOTEST HT56 Combustible Gas Detector Liquefied Petroleum Gas Natural Gas Alarm1. Widely used in gas pipeline leak detection, household gas prevention, gold mining, tunnel mine operations, oil and gas extraction, hazardous goods storage warehouses, etc. 2. It is convenient for users to safely detect various combustible gases, such as: methane, carbon monoxide, gasoline, ethylene oxide, etc. 3. Range: 0 1000PPM 4. Sensitivity: 500PPM 5. Battery: 2x1. 5V AAA batteries (not included in this product) 6. Response time: about 5s 7.