The ThinkPad USB 3.0 Ultra Dock is an universal USB docking solution that not only delivers a premium display experience (up to 4k2k resolution via DP port), but also provides quick and easy connection to all the workspace peripherals you use every day. Simply plug in a single USB 3.0 cable into your Lenovo PC for instant access to up to two external monitors, USB ports, Gigabit Ethernet, headphones/speakers, USB printers, scanners, keyboard, mouse and so on for daily use. The Dock can also charge your mobile devices via two USB always power on ports.Dock requires included AC power to operate.