Features:

1.Micro SD Card + SD Adapter

2.Plug and play (no software needed)

3.Micro SD + TF format,High-speed read and write

4.Storage size 2GB,4GB,8GB,16GB,32GB,64GB,128GB,256GB

5.Applies to Cell Phones, Cameras, MP3/MP4 Player and More device

6.Comes with Adapter to Bring to SD Card

7.Can be Used as Micro SD or SD Card

8.Operating Temperature -13º F to 185º F (-25º C to 85 º C)

9.Storage Temperature -40º F to 185º F (-40º C to 85º C)

10.Original high quality flash memory

Speed:

4GB/8GB-Class 6-SDHC

8GB/16GB/32GB-Class 10-SDHC

64GB-Class 10-SDXC

Class 6: Read speed around 15-20MB/S ,Write speed around 6-8MB/S

Class10: Read speed around 15-30MB/S ,Write speed around 9-12MB/S

About capacity:
4GB=approximately 3.6GB-3.8GB

8GB=approximately 7.4GB-7.6GB

16GB=approximately 14GB-15GB

32GB=approximately 28GB-30GB

64GB=approximately 58GB-60GB

128GB=approximately 120GB

This is calculation difference between manufacturer and our PC,just for you reference.