This 2 Port ExpressCard eSATA Controller Card offers provides two eSATA ports, allowing you to connect eSATA external SATA storage to your laptop computer through an ExpressCard port. The ExpressCard eSATA controller features port multiplier support with FIS-based switching, allowing multiple eSATA hard drives to be accessed using a single eSATA port. Plus, the adapter card uses a native PCI Express (single) chipset that provides enhanced compatibility, reliability and performance for external storage applications, with support for high speed eSATA data transfer rates of up to 3Gbps.