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What is the different between a class 10 micro SD card and class 4? Is there some changes in the circuitry or the materials used in manufacturing? - Quora
Amazon.com: SanDisk 32GB MicroSDHC High Speed Class 4 Card with MicroSD to SD Adapter : Electronics
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Amazon.com: SanDisk 32GB MicroSDHC High Speed Class 4 Card with MicroSD to SD Adapter : Electronics