Probably it's GBA/DS or DS only flashcard called M3 Lite Professional or Perfect (?).
https://www.emuparadise.me/reviews/M3 Lite/
https://gbatemp.net/threads/m3-lite-professional-review.39966/
https://gbatemp.net/threads/the-ultimate-m3-perfect-gba-guide-final.336658/
No it's not like that. I'm using standard, 2GB microSD card (with miniSD adapter) on my first generation EZ-Flash IV (firmware v. 2.05) and everything is good.
I've been playing Killer Clowns from Outer Space all day, is pretty fun. Basically Friday 13th but with clowns. One of my favorite b rated movies from way back.