RT55SN25HX RAID Tower V25 (black color) with four HPM-XA system Version and five Snap-In Disk Array25. Install up to twenty 2.5" SATA hard drives or SSD of any capacity (drives not included). Drives are added or removed like tape cartridge from each drive bay with no special tool required. Connect to system via four eSATA ports (connecting cables included). Drives can be configured as RAID0, RAID1, RAID3, RAID5, RAID10, JBOD, Clone Mode using built-in hardware RAID. For more detail, please review the following product web page http://www.addonics.com/products/rt55sn25hx.php