Western Digital My Book Essential Edition, 1 TB. Hard drive capacity: 1000 GB, Hard drive rotational speed: 7200 RPM, Hard drive interface: USB 2.0. Weight: 1.15 kg, Width: 54 mm, Depth: 137 mm. Operating temperature range (T-T): 5 - 35 °C, Storage temperature range (T-T): -20 - 65 °C. Data transfer rate (max): 480 Mbit/s, Power requirements: 100-240 VAC