This CO2/ARGON gas pressure regulator allows reducing the pressure of gas coming from a bottle to the desired level. It is compatible with typical U.S. standards and can be used on most MIG welding machines. Features • Flowmeter is back-pressure compensated to ensure accurate readings when line restrictions are present • Design for Argon, CO2 gas bottle with W21.8 outlet • Allows to reduce the pressure of gas coming from a bottle to desired level • Polycarbonate flow tube and outer cover are impact resistant for maximum durability • Twin pressure gauge, easy to read, helps adjusting the outlet pressure in high precision • External safety valve equipped, auto released outside if the pressure over safe level