Specifications Material: Aluminum alloy housing, premium chip Card Slot: SD/Micro SD(TF card) Supported Card Types: SD/SDHC/SDXC/Micro SD/Micro SDHC/Micro SDXC/MMC Connector: Type C(USB C)/USB 3.0/Micro USB Operation System: For Android, Mac OS, Windows 10/8.1/8/7/Vista/XP, Linux Supported Devices: PC with USB or USB type C, Android smartphone, tablet with USB OTG function, other USB type C interface, such as iPad pro About capacity: 16GB=approximately 14GB-15GB 32GB=approximately 28GB-30GB 64GB=approximately 58GB-60GB 128GB=approximately 117GB-124GB 200GB=approximately 182GB-186GB 256GB=approximately 230GB-249GB 512GB=approximately 460GB-499GB 1TB=approximately 920GB-980GB Vendors are using Flash memory decimal arithmetic: 1 MB = 1000KB, 1G = 1000 MB Calculated, operating system with binary arithmetic: 1 MB = 1024KB, 1 GB = 1024 MB; So there are some differences between display capacity and nominal capacity of flash memory products