Detecting steps Power on In a clean and contamination-free environment to turn on. Warm up time The analog bar scrolls on the screen about 30s after the gas leak detector switch on. When you hear 2 times beeper "beep", and the analog bar stops scrolling, it means preheat finished. Starting detect Now, this portable gas sniffer can be used to detect whether the combustible gases leak or not. Detect Flammable Gases Many kinds of combustible gases, such as natural gas, methane, ethane, propane, butane, carbon monoxide, gasoline, petrol, coal gas, gas oil, sewer gas, alcohol, ketones, and more. Supersensitive probe In the design process, we adopt the upgraded chip and tested methane as a reference. Its sensitivity is 50ppm, response time is 2 seconds only. The sooner we recognize the danger, the safer our lives. 8 LED indicators - All LED indicators off: 0-300 ppm - Green indicators light up: 300-1500 ppm - Yellow indicators light up: 1500-5000 ppm - Red indicators light up: >5000 ppm Portable and Convenient Compared with a detector installed permanently in your home, you can hold it to detect anywhere you want. Large LCD Screen Can see the temperature and humidity of the current environment clearly. Wide application Home natural gas, gas pipelines, gas storage tank/cylinders, propane gas grill/stoves, exhaust gas and fuel leaks, cabin leaks etc. Feature: Various combustible gas detectorTemperature and humidity sensor3-Mode alarmCelsius and Fahrenheit switchable8 LED indicators in 3 colorsAuto power off and low battery indication Package include: 1 x Handheld Combustible Gas Tester 1 x Carrying Case 1 x Screwdriver 2 x AAA Batteries 1 x User Manual