Accessory | Nintendo GameCube | SD2SP2 Adapter SD Card Player
for the Nintendo GameCube
The adapter plugs into the spare serial port 2 slot underneath the console called the SP2 slot. You can then simply load your favourite homebrew or games roms from an SD card and lanch it though the popular Swiss tool set.
Recommended: You're wise to modify your console in advance with a XenoGC modchip, then you can simply boot the Swiss disc and access the games you've installed on SD card on the SD2SP2 adapter.
Don't be put off with the complexity, as it's all really easy and straightforward once it's running.