For high speed action recordings This microSD memory card's extremely fast speeds enable fast transfers, high app performance and high quality recordings in the 4K UHD format. The card supports 4K UHD videos, Full HD videos and images with high resolution. This makes it the perfect choice for Android smartphones, action cams and drones. The super fast SanDisk Extreme PRO microSDXC storage card reads up to 170 MB/s and writes at up to 90 MB/s. It is also A2 classified, which means that it enables high application performance and improves your smartphones functionality.