Here are the types of CO2 and HPA systems we carry.
Cartridges are the most affordable CO2 option available. Cartridges are measured in grams and are single use - once you put them in your paintball or airsoft gun, you'll want to use up all the gas that's in them because there's no way to seal them back up. CO2 cartridges are disposable.
CO2 tanks are the most affordable refillable option for powering a paintball gun. They can be filled at your local paintball shop or field, as well as at some sporting goods stores. CO2 tanks are a great option for players who live in remote areas, as well as for players with entry-level or older mechanical markers.
High Pressure Air - HPA for short - is now the most common way to power a paintball gun. HPA tanks are more expensive than CO2 tanks, and you'll want to make sure you'll have access to a paintball shop or field that can refill them for you. You may also see HPA referred to as Compressed Air.