Seagate STAR401 BlackArmor NAS 400 Network Storage Server Small-business network storage solution provides optimum uptime and data integrity for up to 50 workstations Designed for optimum uptime and availability Customize to grow with your business - install up to four drives (drives sold separately) Create full-system back ups of PCs and use Time Machine software for Mac computers Two Ethernet ports, four USB 2.0 ports