The size of the SD card can technically be ANY, it's just more convenient if you want to fit multiple games on the same SD card before installing. The size is up to you, but yeah after installing everything you can even use a 2 GB.So I recently modded my Wii U using this guide (thanks MattKimura! you're awesome!) and I had a question regarding the size of the SD card. While it appears that I need a 16GB or higher SD to install games, is that necessary after modding it? What I mean by this is after I finish downloading games, or if I just don't want any games for whatever reason, can I use a smaller SD card, say 2 or 4 GB's? I noticed that the install files take up about 1 MB, at most, of space so it would kind of be a waste to use a 32GB SD card (that's what I'm using now) for only 1 MB of files. I was using my 32GB SD card for my Wii and I have an extra 4GB SD card laying around so I was wondering if I can use the smaller SD card without any negative implications. I'm sure there might be some compatibility issues, which is why none of the guides I've read ever mentions or recommends the use of a smaller SD card. Thanks in advance!