12 oz Aluminum CO2 Tank This lightweight aluminum CO2 tank is BRAND NEW from the factory for years of trouble free use. The brand of tank may vary but will be from a major supplier of CO2 tanks; Typically Pure Energy/Extreme Rage (PMI) or Guerrilla Air. A 12oz tank will deliver 500-600 shots per fill on most guns. Actual performance may vary based on gun type, set-up, and individual playing style. Please note: By law, we are required to ship all CO2 and HPA tanks empty. Tanks will need to be filled prior to use.