Chinese AC gas Vs American AC gas!?

So every time when i need to refill my AC with gas i have to put up with this bullshit, sir do you want Chinese or american gas? Chinese for 1200, American for 2600. What the FK i mean how the fk i would know the difference? Can someone explain this? If such a thing really exists and how to spot. I once refilled Chinese in one AC and american in other, i didnt find anyyyyyy difference nor there was a difference in gas cylinder apart from name n logo.

Gas cylinders are all the same.. they are refilled with anything you want, even cng or lpg...

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