Elgato Thunderbolt 2 Dock - With 50 cm Thunderbolt cable, 20Gb/s, 4K support, 2x Thunderbolt 2, 3x USB 3.0, audio input and output, Gigabit Ethernet, aluminum chassis Connect everything to your MacBook or Ultrabook at once. Two Thunderbolt 2 ports, to daisy chain up to 4 more Thunderbolt devices Built-in HDMI port: directly connect one display with up to 4K resolution; dual displays only supported when using a native Thunderbolt display and HDMI connector. Built-in Gigabit Ethernet: enjoy increased network performance Three USB 3.0 ports: high-power device support for iPad, SuperDrive and more. Stand-alone USB charging: keep charging when your computer is not connected. Separate microphone input and amplified audio output Included software: conveniently eject all storage devices at once.Note that the Elgato Thunderbolt 2 Dock does not provide power to computers NOTE : If you have a Thunderbolt monitor, you can connect a second display to the Elgato Thunderbolt 2 Dock using the HDMI connector.