A small CO2 cartridge is held by this apparatus which spins when
the cartridge is discharged. To discharge the CO2 cartridge, use
the black cylindrical device pictured in the photo. Pull back on
the knob until it locks, place the other end against the CO2
cartridge as it is held in the apparatus, and then push the button
on the side of the black cylinder to discharge it. Hold it steady
against the apparatus when you do so that the CO2 cartridge gets
punctured.
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