This 5 lb. Aluminum CO2 Tank cylinder is produced from high strength aluminum alloy. Enjoy the benefits of aluminum tanks - they are lighter than steel tanks and do not rust! Remember, the tank must be used in a fully upright position, so do not tilt it or lay it on its side. Easy to fill; simply check out your local listings under "Gas," or try local fire extinguisher supply or welding supply companies. Features: Made of high quality aluminum. MATERIAL: Every cylinder is produced from high strength aluminum alloy 6061-T6. MARKINGS: Cylinders are stamped with required U.S. Department of Transportation (DOT) and Transport Canada (TC) Markings.FINISH: Brushed body with natural unpainted dome is standard. Specs: Dimensions: 5 1/4"D x 18"H. TARE Weight: 7.7 lb. Holds 5 lb of gas. Capacity: 6 - 8 half kegs. Service Pressure: 1800 PSI / 124 BAR. Test Pressure: 3000 PSI / 207 BAR. CGA 320 valve. Shipping: Tanks shipped EMPTY. We cannot ship these, or any other tank filled.