... Grade:99.99%-99.999% 2. usage:Electronics equipment,transformer,refrigerating fluid the 3.best quality ,the cheapest ... colorless, tasteless, odorless, non-toxic, non- burning gas with very good stability, heat resistance, excellent electrical insulation ... industy ect.It is a good cleaning gas and etching gas for plasma process.---------------------------------------------PURITY 99.99% 99 ...