If you order from Nintendo, be careful. A while back Nintendo stopped making DS cases with the GBA slot. I heard somewhere that they no longer offer the ones with the slot in their site. They might, but just make sure that you order the right ones. They have 3rd party ones on amazon and various online stores - they run from crap to decent quality, just note that some 3rd party cases have trouble fitting the GBA games, and will bulge open due to crap design. Just read the reviews before ordering. I'll see if I can find the sites I;ve ordered from in the past