●Capacity options: USB 2.0:4GB 8GB 16GB 32GB 64GB USB 3.0:8GB 16GB 32GB 64GB ●Read write speed: Interface type: USB 2.0 Write speed: 5mb/s-8mb/s; read speed: 10mb/s-15mb/s. Interface type: USB 3.0 Write speed: 15mb/s-20mb/s read speed: 40mb/s-80mb/s. ●Friendly tips: The actual available capacity of the datastore is less than the capacity listed on the product. Because some of the capacities listed on the flash device are used for formatting and other functions. Therefore, the actual amount of memory is as follows: 4GB: about 3.74gb, 8GB: about 7.44gb, 16GB: about 14.6gb, 32GB: about 29.2gb, 64GB: about 58.5gb ●Customer Service： Please feel free to contact us for any product quality problems or unpleasant shopping experience. We will reply to you within 24 hours and provide you with the best service. Professional after-sales team, ready to serve customers.