
All tested to ensure they all work. You have done everything. Did a speed test and they were very slow when writing compared to my Kootion 32gb. For example 10MB/s versus 55MB/s on Kootion. The read speed is around 80MB/s, the same as Kootion. The Revain site doesn't claim write speeds, just the usual 100MB/s for class 10, which no one sees, probably due to the low write speeds. I looked through the reviews and found others who had the same problem. I don't think I will buy these again.

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