Nitrogen makes up 78% of the Earth's atmosphere and is a non-toxic, stable gas. NitroAir can be used with N2 designated airguns in both hot and cold temperatures, which is a benefit that CO2 doesn't offer. NitroAir means you don't need an expensive air compressor or an airgun hand pump that results in a sweaty workout just to get some trigger time. Stock up on NitroAir cartridges and keep them in a cool, dry location. They'll be ready to use for many, many years.