MicroSD Memory Card 64GB EVO Plus Flash Mini SD Card 32GB 64GB 256GB 512GB Class 10 UHS-3 High Speed MicroSDXC

About capacity:


16GB=approximately 14GB-15GB

32GB=approximately 28GB-30GB
64GB=approximately 58GB-60GB
128GB=approximately 115GB-119GB
256GB=approximately 230GB-238GB

This is calculation difference between manufacturer and your PC, please Google 'Memory card capacity' to get more information.
Your PC says 1GB = 1.073741824 Billion bytes where Market Defines 1 GB = 1.00 Billion bytes.

Regarding the speed：

The speed in our detailed picture is the highest speed of the memory card. Each one has been tested before shipment, ensuring high quality.

Package :


1 X Micro sd card with free adapter + Retail package


Specs:


All cards are Class 10, UHS Speed Class 3, Video Speed Class 30. 

Sequential write speed is minimum 30mb/s. These can easily record 4k video.