this fimrware is for the r4i3ds cars.
cards might vary a little in design, but should have web address http://www.r4i3ds.com printed on card.
card updates are done via the card firmware on this card.
it is not clear on the official card website,
but i would imagine this card can be used on:
1. any dslite
2. dsi 1.4.3 or below
3. 3ds 3.0.0.-6 and below