Co2 gas comes in a metal capsule under pressure and and needs a special magazine for it. The capsule takes over as the reservoir in the gas magazine.The CO2 capsules are inexpensive and used only once but are easy to change and work well in cold weather.People tend to change out the gas before it is completely use up and with experience can tell now many mags it will use before the gas is exhausted.
This gas comes in larger cannisters and can be bought in red ,green and black gas. The difference being the pressure so again check the pressure of your gun and make sure it is the correct gas you are using. We offer a few different makes.
As above some pistols can use both green or co2 but make sure you follow the manufacturers guide lines. Remember in cold weather gas guns can freeze up.
Red or black gas is more powerful and will increase the velocity of your gun so be careful and test the guns speed with a chronograph.Using the more powerful gases can damage you gun if it is not designed for these gases.Experiment with gases and see which one fits into your game and is compatible with your weapons.