Avolusion Portable Storage System (HD250U3-Z1) 320GB Ultra Slim 2.5" SuperSpeed USB 3.0 Portable External Hard Drive (Black) is designed to attract the eyes of user at a glance with durable chassis external hard drive. The Avolusion HD250U3-Z1 320GB Hard Drive endeavors top quality design in durable case, with slim trimming, which make the Avolusion HD250U3-Z1 320GB 2.5" USB 3.0 External Hard Drive a fine piece of storage device on your palm. You can connect these to your USB 3.0 (or USB 2.0) port to expand your Windows OS Laptop or Desktop storage capacity instantly! It is fully compatible with any Windows OS. (Windows NTFS Pre-Formatted). SuperSpeed USB 3.0 Transfer Rate up to 5.0 gbps extreme fast performance!