Get extreme speeds for fast transfer, app performance, and 4K UHD.2 Ideal for your Android? smartphone, action cameras or drones, this high-performance microSD? card does 4K UHD video recording, Full HD video and high-resolution photos. With up to 400GB1, the super-fast SanDisk Extreme? PRO microSDXC? UHS-I memory card reads up to 170MB/s* and writes up to 90MB/s*. Plus, it?s A2-rated, so you can get fast application performance for an exceptional smartphone experience.