2 ms·It's called a Nintendo DS game card. I don't know if the Switch game cards are flash or mask-ROM.by mrguyorama 3y agoIt's called a Nintendo DS game card. I don't know if the Switch game cards are flash or mask-ROM.monocasa 3y agoMask ROM.TapamN 3y agoI don't have a source, but I think I remember reading somewhere that Switch games are some kind of archival flash, designed for 50+ year retention.