Dual Bay 2.5/3.5" SATA HDD RAID External Enclosuren a digital world, it is important that you have your precious files backed up. If the hard drive in your computer fails or your computer is stolen, you will be thankful that your photos, documents and other important files are backed up to this RAID system. The RAID (redundant array of independent disks) feature allows you to have files stored on two hard drives, either RAID 0 (Striping) mode for best performance or RAID 1 (Mirroring) for protection