helium cylinder Standard: GB5099/ISO9809 Type: WMA219-8-15 O.D.: 159mm Capacity: 8L Gas capacity: 6CBM Design wall thickness: 3.6mm Weight: Approx.11kg WP: 15MPa TP: 25Mpa The seamless steel gas cylinder are all made of high quality steel, and are supposed to be used repeatedly for keeping permanent gases, such as oxygen, hydrogen, argon, krypton, nitrogen; and high-pressure liquefied gases, such as carbon dioxide and ethylene. They can be used in industry, agriculture, medical treatment, scientific research and analytical instruments.