Zebra DNA Luxfer L6X Aluminum CO2 Tanks with CGA320 on/off Valve (Natural, 5 LB) Cylinders are made from Luxfers exclusive L6X alloy, a proprietary version of 6061-T6 specially optimized by Luxfer metallurgists to improve its durability, fracture toughness and resistance to tearing and cracking. More than 40 million L6X cylinders in service around the world have an exemplary record for safety and dependability. Highly corrosion-resistant interior and exteriorideal for wet gases Cylinders perform well at low temperatures. Lightweightup to 40 percent lighter than comparable steel cylinders. Consistent weight. Thick, consistent walls resist damage. Cylinders meet or exceed all regulatory standards worldwide. Luxfers exclusive Safety First training program that provides manuals, inspection guides, safety bulletins, reference materials, shop posters, videos and other training materials free of charge to promote safe use, storage and inspection of aluminum beverage cylinders. Consistent with Luxfers position as the world's leading manufacturer of high-pressure aluminum gas cylinders, educational offerings are available in multiple languages and formats. Cylinders cycle-tested in excess of 100,000 cycles at service pressure. Minimum burst pressure tested to 2.5 times service pressure without failure