There's a review of this pad right here (https://nfggames.com/forum2/index.php?topic=7599) if you'd like to know more about it.
I was impressed at how perfectly 8BitDo copied this pad. The thumbstick assembly is almost perfectly identical to the original pad, with only a few modifications. Externally it feels the same, but with new shoulder buttons and three functional buttons - one by the USB port, two more on top.
Anyway, here's the inside view. 8BitDo on the left, original SNK on the right.
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