Western Digital SN520 256GB M.2 2280 NVMe SSD Drive – Electronics Outlet: Open Box New & NEW Electronics, TV's, Computers, Tablets, Printers and Networking Gear
Can confirm the Western Digital SN520 256GB NVMe drive is compatible with the Deck : r/SteamDeck
WDC PC SN520 SDAPMUW-256G SSD Benchmarks - NotebookCheck.net Tech