Warning to anyone buying Samsung SD cards off of eBay. They are made in Korea, so always check the back of the card (real on the left, fake on the right) :
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Recognize fake and original samsung micro SD
MB-ME512KA/AM | EVO Select + Adapter microSDXC 512GB | Samsung Business US
HOW TO IDENTIFY A FAKE SAMSUNG MICRO SD MEMORY CARD - Phoneparts
MicroSDXC EVO Select Memory Card w/ Adapter 128GB Memory & Storage - MB-ME128GA/AM | Samsung US
Cheap SD Cards from eBay are Fake - Raspberry Pi Spy