Hi All,

IPC-2221 9.2.2 Annular Ring Requirements states:

"The minimum annular ring on EXTERNAL layers is the minimum amount of copper
(at the narrowest point) between the edge of the hole and edge of the land
AFTER PLATING of the hole"

"The minimum annular ring on INTERNAL layers is the minimum amount of copper
(at the narrowest point) between the edge of the drilled hole AFTER DRILLING
the hole"

I am confused as to why there are two definitions. Can anyone help?
I have a few Ideas of my own, but would appreciate an explanation.

Best Regards,

Mark

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