$23.99@amazon.com
1. The unit comes with an SD adapter. As a result, it is usable for many electronic devices.
2. The speed is fast for a Class 4.
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The write speed range is between 2.8-5.3 mb/s. Most of the write activity is at 4.0 mb/s.
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The read/data transfer rate is between 13 and 25 mb/s. Most of the transfer activity concentrates at 19 mb/s.