How to read plate thickness from 10GA, 12GA, 16GA?

Dear Everyone :
I am not really sure if this topic supposed to pot here. But this forum is the most close one I can find…
My company always receive prints from the States and enigneers like to use 8GA, 10GA, 12GA… instead of thickness. Based on limited information I got, I think thats used in determined wire diameter( for example, 8GA = xxx mm wire ). But I have found different diameter for the same spec, for example, several thickness found for 10GA. I am really confused… :blush:
I would be really appreciate if any have an idea or suggest a direction for me to find a comparision table. Thanks. :notworthy:

Here, try this on for size.
you’re welcome

Thanks for your reply. Thats very helpful for me. :notworthy: