HGST 7K4000 4TB SAS 20 Pack, Ultrastar. Hard drive capacity: 4000 GB, Hard drive interface: SAS, Hard drive speed: 7200 RPM. Power consumption (read): 10.9 W, Power consumption (write): 10.9 W, Power consumption (idle): 6.2 W. Width: 4" (101.6 mm), Height: 1.02" (26 mm), Depth: 5.79" (147 mm). Data transfer rate: 6 Gbit/s