80 cf Welding Gas, Welding Cylinder, Welding Tank for Argon Nitrogen Argon/CO2 Helium Current 10 yr Hydrotest stamp Comes with a CGA-580 valve for Argon Nitrogen Argon/CO2 Helium DOT required cylinder cap No gas service shoulder labels shipped with cylinder DOT 3AA cylinder CYLINDER SHIPPED EMPTY Cylinder Size 7" O.D. x 32" Length Weight Empty 46 lbs. This cylinder is typically used for nitrogen, helium, argon, and argon / carbon dioxide mixes.