1TB Canvio Slim II Portable External Hard Drive (Mac Model); Specification: Capacity: 1TB, Interfaces: USB 3.0 (backwards compatible with USB 2.0), Interface Transfer Rate: Up to 5 Gb/s (USB 3.0), Up to 480 Mb/s (USB 2.0), Speed: 5400 RPM, Average Seek Time: 12 ms, Cache Buffer: 8 MB