Verbatim 3.5" NAS Hard Drive 500GB. Total storage capacity: 500 GB, Hard drive capacity: 500 GB, Hard drive size: 88.9 mm (3.5 "). Compliance industry standards: IEEE 802.3, IEEE 802.3u, Supported network protocols: DHCP, SMB/CIFS, Samba, NFS, NTP, UPnP, WINS, Networking features: Ethernet, Fast Ethernet. Power requirements: +5V; +12V. Weight: 1200 g. Compatible operating systems: Windows 98SE/Me/2000/XP Linux 2.4 + Mac OS 8.6.9.x Mac OS X 10.1 +, Minimum system requirements: CD-ROM