WD  250 GB External USB 2.0 Hard Drive with Dual Option Backup ??Dual-option Backup  choose how and when to back up your data, automatically or on-the-spot ??USB 2.0 interface  high-speed connection for maximum throughput ??Front-mounted power button  equipped with WD's exclusive Safe Shutdown feature that ensures all data has been safely transferred before shutting down the drive ??7200 RPM rotational speed ??Preformatted*; simply plug it in and go