The Sandberg Multi Hard Disk Box 3.5" lets you use a 3.5" IDE or SATA hard disk as a portable external hard disk. The box connects to your computer either via USB (Universal Serial Bus) 2.0 or e SATA, giving you speeds of up to 3 Gb per second (IDE hard disks cannot, however, be connected with e SATA). If your computer doesnt already have e SATA, you can use the adapter bracket supplied to convert an internal SATA port to an e SATA port. The aluminum case & the quiet built-in fan keep the hard disk cool, guaranteeing you optimal performance.