Raidsonic iS2880-8S-U5D. Total storage capacity: 4000 GB, Hard drive interface: SAS & SATA, Hard drive size: 63.5 mm (2.5 "). Weight: 1.66 kg. Compatible operating systems: Windows XP/Vista/7/Linux. Dimensions (WxDxH): 146 x 183.5 x 85 mm