eSATA II PCIe Pro Easily adds 2 external (eSATA) ports to your PCIe equipped desktop. PCI Express 1-lane (x1) SATA II adapter works with PCI Express slots with different lane width Supports hard disk hot-plugging PCI Express-enabled system with an available PCI Express slotWindows 7 (32-/64-bit) / Vista (32-/64-bit) / XP (32-/64-bit) / Server 2003 & 2008 (32-/64-bit) / 2000Mac OS X v10.4.9 to 10.5.6, 10.6.x