Miworks 64GB Micro SD Card Specifications: Interface: MicroSDHC/XC class 10 UHS-1 Grade: C4/C6/C10 *Running out of storage in your phone? with Miworks 64GB SD you can store up to more then 500 files. * Backup your phones Data with Miworks 64GB SD Card. *Speed based on USB 3.0 UHS-1 card reader Actual Transfer speed may vary due to host hardware, software and usage.