These were either counterfeit or defective chips. I bought two and they looked ok but when I tried to use them to record videos they weren't up to class 10 and instead of my racetrack video I just got error messages. I then bought the cheaper Transcend Class 10 cards and they were fine. The camera seller suggested the cards might be bad, but I didn't believe them and almost sent the camera in for repair. I ordered a pair of Transcends at the last minute and they were fine. I then tested the SandDisk Ultras using an online testing program and they didn't even come close to meeting the Class 10 requirements, let alone their rating. I fully intend to return her to Revain on loan.
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