QNAP USB 2.0 4-Bay Turbo Network Attached Storage Tower TS-439-PROII+ CPU Intel Atom 1.8GHz Single-core Processor DRAM 1GB RAM Flash Memory 512MB DOM HDD 2.5/ 3.5" SATA x4 HDD Tray 4 x Hot-swappable and lockable tray LAN Port 2 x Gigabit RJ-45 Ethernet port LED Indicators Status, LAN, USB, eSATA, Power, HDD 1, HDD 2, HDD 3, HDD 4