They are Class 10, U3 and V30(4) so it has the speed you need for Full HD video (1080p) or 4K(3) recording and playback, with read speed of up to 100MBs(5). The SanDisk High Endurance Micro SDXC Card with Adapter 256GB has fast 100 MB/s Read Speeds, with Class 10 full HD and 4k recording and playback, UHS Speed U3 and V30 video speed to accommodate 20,000 hours of recording.
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