... supply all kinds of high purity gas, such as oxygen,argon, nitrogen, CO2, helium, etc. ProductspuritystandardunitApplicationoxygen≥99.5GB-T3863-1995bottle/cylinder Steel ... processingnitrogen≥99.5GB-T3864-1996bottle/cylinderReplacement gas and protection gas for chemical industry, metallurgy, and electric industry.hydrogen≥99.9GB-T3634-1995bottle ...