Pocketec DataStor Mini 20GB USB 2.0 Ultra-Portable Hard Drive (Model 555) 20 GB storage capacity, Hi-Speed USB 2.0-certified Up to 16 MB/per second sustained read/write speed; up to 480 Mbps maximum transfer rate Requires no power supply: completely bus powered by your USB port You can stack multiple DataStor Mini drives for greater storage Multi-platform compatible: PC, Macintosh, DOS, and Linux; no drivers required for Win 2000+, Mac OS 10.1.x+, and Linux