Ten pack of CO2. Be sure of proper fit and seal with genuine powerlet 12-Gram CO2 cartridges. Exacting tolerances ensure consistent performance in virtually all gas operated guns. For those using CO2 powered devices, these 12 Gram CO2 Cartridges provides a reliable source for launching your projectiles. Made with a solid seal, these CO2 Powerlets are designed to provide consistent, reliable performance. 12gram CO2 Cartridges are compatible with any airgun, airsoft gun, paintball gun or other devices that require 12 gram CO2 cartridges. Whether you are target shooting with Airsoft BBs or playing a paintball tournament, your rate of fire can be as fast as you are ready to make it