Designed for microSD devices such as smartphones, interchangeable-lens cameras, drones, or GoPro action cameras that can capture Full HD, 3D, and 4K video, as well as raw and burst photography, the 128GB Extreme UHS-I microSDXC Memory Card from SanDisk has a capacity of 128GB, is compatible with the UHS-I bus, and features a speed class rating of V30, which guarantees minimum write speeds of 30 MB/s. If your device does not support the V30 standard, this card also supports the U3 standard, which also guarantees minimum write speeds of 30 MB/s. Read speeds are supported up to 160 MB/s and write speeds max out at 90 MB/s.

While this card has been designed for cameras that are UHS-I / V30 / U3 compatible, it may be used in devices that do not support UHS-I / V30 / U3. However, bear in mind that this card will then default to your device's speed class and bus rating, such as UHS-I and U1, which supports minimum write speeds of 10 MB/s, or Class 10, which also supports minimum write speeds of 10 MB/s.