The PEXUSB3S4V PCI Express USB 3.0 Card (with SATA Power) adds 4 external USB 3.0 ports to any PCI Express-enabled computer system. SuperSpeed USB 3.0 provides up to 5 Gbps of data bandwidth, while remaining backward compatible with existing USB 2.0 devices at 480Mbps. Using a stacked port layout that places the ports one on top of the other, more ports are able to fit into a smaller space. This 4-port PCIe USB 3.0 adapter enables all four USB 3.0 ports to be external facing, while still allowing the card to fit into a small form factor/low profile computer system. Plus, with a built-in SATA power connector, each USB port can provide up to 900mA of power to devices that draw power from a host bus connection (500mA for USB 2.0) by connecting to your computer power supply. The PEXUSB3S4V USB 3.0 PCIe card is backed by a StarTech.com 2-year warranty and free lifetime technical support. 4 external USB 3.0 ports in a stacked layout. Fully compliant with USB 3.0 revision 1.0 specifications and Intel xHCI rev0.95 specifications. Built-in optional SATA power connector for bus-powered USB devices. Optionally provides up to 900mA per USB port. Backward compatible with USB 2.0 and USB 1.0/1.1 devices. Compliant with PCI Express 2.0 specifications. Includes a Low Profile/half-height installation bracket. Upgrade an older PCIe-based system with USB 3.0 connectivity, to fully utilize USB 3.0 devices. Expand a system's USB capabilities with four additional external USB ports, for connecting additional external hard drives, CD/DVD drives, MP3 players, printers, scanners, webcams, game controllers, digital cameras, etc.