From Manufacturer
Designed for photographers and digital media professionals, the PRO Ultimate UHS-I microSDXC Card from Samsung features a storage capacity of 256GB and takes advantage of the UHS-I bus to support read speeds up to 200 MB/s and write speeds up to 130 MB/s. Its V30/U3 class rating guarantees write speeds won't drop below 30 MB/s, making it suitable for 4K, Full HD, and 3D video, as well as raw and JPEG captures, plus rapid shutter bursts.
Aside from support for UHS-I, V30, and U3, Samsung also built this card with support for the Application Performance Class 2 (A2) spec, which includes optimizations to give Android users an improved mobile experience, delivering faster mobile app performance. The A2 spec allows the card to manage random read input-output access per second (IOPS) operations so it can quickly open apps and process accompanying tasks, such as audio, graphics, saved profiles, and in-app permissions.
As with most Samsung cards, this memory card is resistant to water, X-rays, magnets, drops, and wear. It is also able to withstand temperatures from -13 to 185°F so you can take it with you into extreme environments, including snow and deserts. Included is a USB-A card reader so you can download content from the card to your computer.