These Umarex-Walther 88 gram CO2 cartridges comes two per pack. Great quality CO2 runs clean in your airguns and fit air rifles such as the Umarex AirJavelin, Umarex Fusion 2, 850 Air Magnum and 850M2. 88-gram CO2 cylinders provide longer shooting sessions. We recommend that you use all the CO2 and that you not leave pressure on the seals of your airgun for more than a day or two. It's a good idea to put a drop of silicone oil, like RWS Chamber Lube, on the tip of the capsule before inserting it to keep the seals lubricated and the internals of your pellet rifle in good working condition.