Byrna's box of nine 8g CO₂ cartridges are custom fit for the Byrna HD Launcher. Now also including 1 CO₂ cartridge with oil for simple maintenance every 10 CO₂ cartridges used (please note this not the same as the Byrna Oiler Kit, this is a special oil-filled CO₂cartridge used on the Byrna HD Launcher for maintenance every 10th cartridge).

Each cartridge (new) will be good for 15-20 rounds (4 mags in a 5 round magazine) at full speed. Punctured cartridges within the Byrna HD will leak over time.

It is recommended to swap out punctured CO2 cartridges and leave an un-punctured cartridge inside the Byrna HD to avoid any compressed air loss. The Byrna HD will puncture and fire the first round at the same time.