The R4i card is the R4 card that can be used in conjunction with consoles such as the Nintendo DSi and Nintendo DSi XL console. They are not compatible with the most recent console release, the Nintendo 3DS(for this you need a R4 3DS card). If you have a Nintendo DS or Nintendo DS Lite, then your preferred card should be the R4 SDHC
A R4i card or a R4 adaptor as it’s referred to is a device that communicates with the console and the Micro SD memory card that fits into the back of the device. Without the memory card at the rear of the R4 card, the r4i card would not be able to function as it itself has no storage capacity. The R4 card itself is exactly the same size as the standard DS console game but at the rear of it is a slot which allows a micro SD card to be inserted.
PLEASE NOTE: No R4i card can function without a memory card. If you do not purchase a memory card, you will be required to download and install the software for your R4i card yourself.