About Product:Generally, Hard Disk Dock of the Two Card Positions Can Be Directly Copied from One Disk to Another without Connecting to a Computer.Hard Disk Is One of the Main Storage Media of Computer, Which Consists of One Or More Aluminum Or Glass Discs. The Disc Is Covered with Ferrimagnet. Hard Disks Include Solid State Disks, Mechanical Hard Disks, and Hybrid Hard Disks. Most Hard Disks Are Fixed Hard Disks, Which Are Permanently Sealed and Fixed in Hard Disk Drives.