The 440 is a four-bay NAS device that comes with four, user-serviceable, internal SATA drives, which can be configured as RAID 0, 1, 5, or 10 arrays, or as JBOD (just a bunch of disks). Depending on which RAID mode is being used, drives can be swapped out without needing to shutdown the device--commonly referred to as hot-swapping. The 440 also includes a total of four USB 2.0 ports, which can accommodate additional storage in the form of external hard drives or for attaching a USB-based printer to make the printer accessible to users over a local network. Another feature of the 440 is that it includes two Gigabit Ethernet ports for port-failover or aggregation. Come on by the site and check it out...