About capacity:

Capacity flash memory products are usually shipped in accordance with 1MB = 1000KB, 1G = 1000MB computing, but the operatingsystem using binary arithmetic 1MB=1024KB, 1GB = 1024MB, so there are some differences between the display capacity and standard capacity memory products.This is calculation difference between manufacturer and our PC.

4GB= approximately 3.2GB-3.8GB  

8GB =approximately 6.9GB-7.3GB       

16GB=approximately 14GB-15GB      

32GB=approximately 28GB-30GB

64GB=approximately 58GB-59GB

About writing and reading speed :

16 - 32gb class 10 SDHC;

64gb 128gb class 10 SDXC

Package list:

1x memory card