This dual-bay disk array features swappable hard disks and a built-in RAID controller. No need to set up RAID on your computer, just plug the drive in and start transferring files immediately. The drive arrives preconfigured in RAID 1 to protect your important data - if one drive fails, replace it with an identical drive and the data will automatically rebuild. Leave it in RAID 1 mode for automatic background rebuilding and optimum security for your files, or configure to RAID 0 for increased data reading and writing speeds. Its SATA interface provides a faster boot process and quicker loading of programs and data. Ideal for saving hefty files, video, music, protecting databases or working directly on the drive, it delivers high-capacity performance and data security. Windows XP / Vista / 7 + (32-bit & 64-bit) Mac OS X 10.4.8 + (requires reformatting)