These are Disposable "threaded neck" CO2 cylinders made in Austria.
Austrian made cylinders are the only CO2 cylinders relied upon worldwide by the FAA (Federal Aviation Administration). When you put your professional reputation on the line, you want a CO2 Cylinder that will work perfectly.

Using any other brand of CO2 cylinders will void your lifetime warranty on all our Confetti Cannons. To avoid damaging your cannon, Do not use any silver colored cylinders manufactured by Leland or made in Hungary.

Based on using our Confetti Cannon systems:
If you are shooting streamers, you only need to use 8 gram CO2 cylinders for
maximum effect.
We recommend using 16 gram cylinders if you wish to shoot Confetti to its
maximum Height.