This PCI/PCI Express Expansion chassis expands available expansion slots by providing additional external PCI and PCIe slots that can be connected to a notebook or desktop PC - a cost-effective and time-saving way to swap capability offered by PCI/PCIe add-in cards between mobile and desktop operating environments, or simply add and remove PCI/PCIe cards from the host bus without having to open the computer case.The expansion chassis adds two full length (38cm long) PCI slots (32-bit/33MHz) as well as two PCIe x1 (single lane) to the host computer, through a single PCI Express connection to the host computer.An innovative solution for both PCI expansion and PCIe expansion, the external chassis/enclosure includes a PCIe adapter card which can be installed in any PCIe (x1) slot on a host desktop computer in order to interface the chassis with the computer - in turn allow the host computer to function as though the PCI/PCIe cards were installed directly on the host motherboard.For mobile applications, the PCI/PCIe Expansion chassis can be connected to a laptop computer using StarTech.coms ExpressCard Connection Cable For PEX2PCI4 (EC2PCI), which adds the functionality offered by the PCI/PCIe expansion cards to the laptop and in turn eliminates the expense of having to purchase duplicate adapter cards for the laptop computer.A dependable I/O expansion solution, the PCI/PCIe Expansion chassis is backed by StarTech.coms 1-year warranty and free lifetime technical support.