Air Venturi pre-filled 90-gram CO2 tanks Disposable 2pk * These huge 90-gram CO2 tanks (sometimes referred to as 88 gram CO2 tanks) deliver lots of shots before you need to change the tank. This 2-pack will save you money over buying single tanks and ensures you have a spare when your first one runs out. These 90 gram cartridges have the same external dimensions as 88 gram cartridges.