Product Features: Color: Black Interface: USB 3.0 Capacity: 16GB /32GB /64GB/128GB. USB connection, support hot plug&play. Compatible on both Mac & PC USB service voltage: 4.5v-5.5v. No external power supply requird. Available and various flash adopted. Compatibility:Win98/ME/2000/XP/Vista/Win 7/Win 8,Mac OS 9.x/Linux2.4 or above. Plug and Play. When connect the U-disk to Smartphone ,then you can transfer Datas, Play music and video,File Exchange No need install any software. Writing speed:4-10Mb/s,Reading speed :10-30Mb/s,the rate of performance depends on the different operation system ( We guarantee the reading speed between 10-20mb/s. Before you test the speed of the pendrive, Please guarantee that the usb is put on the 3.0 port of computer. Or the speed of pendrive will be slow.) About capacity 4GB=approximately 3.6GB-3.8GB 8GB=approximately 7.4GB-7.6GB 16GB=approximately 14.4GB-14.8GB 32GB=approximately 28.5GB-30GB 64GB=approximately 58.5GB-60GB 128GB=approximately 110.5GB-120GB 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 Notice: 1.Try to use USB3.0 port to test it, please don't use any 2.0 equipments,sometime the 2.0 system can not test the real speed successful; 2.Do not Insert the pendrive with brute force and frequently,it is easy to damage the plug;do not pull the disk when access to data,or likely to cause data lose;try to pull it after disconnect disk. 3.Please make sure the max capacity your mobile or computer can support,if exceed the max capacity it can support,it can not read the pen drive. Package Included: 1 x USB 3.0 Flash Drive