Western Digital 250 GB USB 2.0 and FireWire External Hard Drive (WDXF2500JBRNN) 250 GB external hard drive 7200 RPM rotational speed and 8 MB cache for maximum storage performance. Built-in USB 2.0 hub with two ports for additional drive connections; two Firewire ports Dual-option Backup--automatic or on-demand Connects to PCs and Macs