Steam Deck has M.2 2230 SSD slot, but Valve does not recommend upgrading it - VideoCardz.com
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Fanxiang S700 M.2 2230 1TB NVMe SSD PCIe 4.0 Unità interna a stato solido, fino a 5000 MB/s, compatibile con Steam Deck e Surface Pro 7+/8/9/X : Amazon.it: Informatica
NEW 2230 SSD 1TB NVMe PCIe for Microsoft Surface Pro X 7+ 8 Surface Laptop 3 & 4 | eBay
WD PC SN530 M.2 2230 1 TB SSD NVMe PCIe per laptop Microsoft Surface Pro X Pro 7 | eBay
WD SN530 m.2 2230 SSD 1TB NVMe PCIe per Microsoft Surface Pro X Surface Laptop 3