The original R4 is limited to microSD cards only (up to 2GB in capacity). The best kernel to use on it would be Wood R4 1.62 as the stock kernel isn’t great to use.

1:1 clones of the original R4 are still being sold on AliExpress. However, it is not recommended to buy them due to the lack of SDHC support.

Setup Instructions (Wood R4 1.62)

1. Format the SD card you are using to FAT32
2. Download Wood R4 1.62
3. Extract the Wood R4 1.62 .zip file to your SD card root.
4. Place any .nds game ROMs you’d like to play into a folder of your choice which isn’t the __rpg folder.
   • (Optional) You may want to create a Games folder to store your ROMs in to keep the root of your SD card organised.