HSETIN HT- 3000 Detect potentially dangerous gas:Natural gas(methane),LPG(propane,butane).when the value exceed the alarm value ,the red light will flicker and beeping. Use our Portable Gas Detector to detect potential gas leaks in pipes, fittings, valves, gas storage tanks, propane barbecue grills, home appliances and hot water heaters. No calibration is required for the lifetime of the product.