This 7 Port USB 2.0 Hub connects to one USB 2.0 port on a Mac or PC computer, adding seven USB 2.0 ports - allowing you to maximize the number of high speed USB peripherals connected to your computer. The hub supports cascaded installation with other USB 2.0 hubs, supporting up to 127 USB 2.0 device connections - a scalable solution for connecting multiple USB devices to a single host computer.The 7 port hub includes a power adapter, but can be powered through USB bus connection to the host computer - allowing you to install the hub as needed without worrying about the availability of a power outlet.