Samsung MB-MP64DA/BBY EVO 64GB Class 10 MicroSDHC with Adapter for $17.95 shipped. Here is a screenshot for reference. Alternatively, it is available at Amazon for $17.95 with free shipping on orders over $49. 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 over $40.