NOTE: Not ok to use on GBB (Gas Blow Back) The "BEST" CO2 adapter in the market. Easily adjust pressure without any tool. Airsoft Gas Comparison Chart Name Other name PSI at 21'C Kg/M2 at 21'C Green Gas Propane ~100 7 Red Gas HCFC-22 ~121 8.5 Regulated CO2 (Without liquid CO2) ~200 - 800 CO2 (With liquid CO2) ~837 58.6 NOTE: Leaking from the "pressure release hole" when you install XC-02 onto a CO2 tank: Here is a way to fix this problem quickly: Install XC-02 onto CO2 tank by clockwise turning down (slowly and smoothly) untill you feel a pressure against to you and stop. Now, try to turn very hard and fast on the last turn. Normally, you can solve the leaking problem. Not all CO2 tank valves are built the same and you need to do with the height of the pin located at the center of the CO2 tank valve. If you still can't solve the leaking problem, you can either buy a new CO2 tank (More than 10 brands you can choose from...) or adjust the height of pin by tools (not suggested.) NOTE: This is a B.B. shower toy. Not an explosive grenade. Everyone should wear goggles in the field and please don't aim at people. Please read the users manual in the box before use.