As support to what ILLusion stated your better off purchasing either the propane adapter or the duster gas adapter, as it stands I do not know how old your guns are but as I understand it the newer Tokyo Marui guns can run propane or green gas straight out of the box, while the older models required upgrades to support the stress of running a heavier gas. Personally I would stick to using duster gas with your guns, but Im gona go ahead and provide additional info just because.
Remeber tetrafluoroethane and not difluoroethane, I believe there is an additive in difluoroethane that has been known to eat away at the O rings.
Not all duster gasses are created the same so keep an eye out.
Just for a quick refrence, green gas and propane are the same, the only diffrence is, is that green gas has silicone oil added already while, propane you have to add it yourself. Green gas also costs more than propane. So the adapters basiaclly pay for themselfves over time
Green Gas = Propane
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http://www.airsoftcanada.com/showthread.php?t=6268)
Anyways, Im sure you probly know how to take care of what you got already but hey, it never hurts to offer a little more info, and maybe you might pick up something you didnt know.
Gas gun maintenance:
http://www.airsoftcanada.com/showthread.php?t=18793
So please if you get a chance fill out some details about yourself in your profile so maybe some of the local guys can hit you up or you can hit them up for help you have any questions or need assitance with something.