Komputerbay 64GB Class 10 UHS-1 memory card microSDXC Pro Grade 1 70 MB / s using Samsung NAND Komputerbay with SD Adapter (Personal Computers)
It is a memory map conforms: a true Samsung made in Korea, not a Chinese clone (though the adapter is him, Chinese ... but that's not important). It is in my Galaxy S4, and it's really great to have so many fast storage.