Samsung MB-MP64DA/BBY EVO 64GB Class 10 MicroSDHC with Adapter for $18.74. Shipping is free on orders over $35. If needed, use this Filler Tool to pad the order for free shipping. Here is a screenshot for reference. Alternatively, it is available at Walmart for $18.74 with in-store pickup. It features up to 48MB/s transfer speed and is waterproof and is compatible with devices with SDHC and SDXC slots. Most places have it for about $23.