Flash memory vendors are using decimal arithmetic: 1MB = 1000KB, 1G = 1000MB calculated, but the operating system is using binary arithmetic: 1MB = 1024KB, 1GB = 1024MB. 
<br />so there are some differences between display capacity and nominal capacity of flash memory products.However, this is allowed to exist. Please do not doubt his authenticity.
<br /> 
<br /> Package Contents:
<br /> Micro SD card with Full Retail Package*1
<br /> 
<br />Speed: 
<br />4/8GB-Class 6-SDHC
<br />16GB/32GB-Class 10-SDHC
<br />64GB-Class 10-SDXC
<br />Tip ( 2.0USB reader Test Result) : 
<br />Class 6: Read speed around 8-12MB/S ,Write speed around 4.5-6.5MB/S
<br /> Class10: Read speed around 10-15MB/S ,Write speed around 8.5-11MB/S