WiiKey / Xeno-Wii ModChip
WiiKey Wired Installation
You can use wires to install the chip if you like this type of installation better. Here you can see the connecting spots better, so re-soldering would be easier if you didn't get it right the first time. With wired installation it would be a lot easier to remove the chip - not that it is needed, but who knows.
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Original WiiKey (not a clone) with a hologram sticker.
Wii Key size compared to a 50 dollar bill.
P.S. The latest chip from the WiiKey Team is called DriveKey - and it is a lot easier to install like a passthrough on the data cable.