PNY P-NSA2-EC-RF 2 Port eSATA II Express Card Connect 2 external eSATA II hard drives to your notebook computer,This card supports data transfer rate of 300MB/second Supports Hot-Plugging and Native Command Queing, 300MB/second is faster than USB, Firewire, or PATA SATA II transfers at up to 2400Mbit/second versus USB 2.0 at 480 Mbit/second ,Supports SATA hard disk hot-plugging Windows Vista compliant, also Windows 2000, and XP The card has 2 External ports (I shaped)