The thermal gas mass flowmeter is designed according to the principle of thermal diffusion. The instrument uses the constant temperature difference method to measure the gas accurately. It has the advantages of small size, accurate measurement, high digitization, and easy installation. The mass flowmeter for gas flow measurement without temperature and pressure compensation is an accurate measurement. The mass flow rate or standard volume flow rate of the gas can be obtained. Compressed air/gas in the boiler room or dryer/carbon dioxide gas in distillery/methane gas in the sewage treatment plant and aeration/generated gas (such as argon, nitrogen, carbon dioxide, helium, oxygen)/gas leak detection.