Sitecom Network Drive 3.5" USB. Maximum capacity: 500GB, Hard drive interface: IDE/ATA, Hard drive size: 88.9 mm (3.5 "). Cables included: USB 2.0 A-B UTP. Operating relative humidity range: 10 - 80 %, Operating temperature range (T-T): 0 - 55 °C, Storage temperature range (T-T): 0 - 70 °C. Compatible operating systems: Windows 2000/XP; MAC OS 10.1.2