Use micro SD card in Galaxy S8 and Galaxy S8+ - Galaxy S8 Guides
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Genuine Samsung Galaxy S8 SIM Tray For G950 Single & Micro SD Memory Card Holder | eBay
Lexar High Performance 64GB MicroSD XC Memory Card 633x UHS-I Class 10 for Samsung Galaxy S8 S9 S10 PLUS + S10e with Mini MemoryMarket MicroSD Memory Card reader - Walmart.com