UtechSmart USB 3.0 4 Port Hub for Ultra Book, MacBook Air, Windows 8 Tablet PC, Backward Compatible with USB 2.0-Silver SuperSpeed USB 3.0 supports transfer rates up to 5 Gbps - The actual transmission speed is limited by the setting of the device connected. Compatible with all Windows and Linux systems. Mac systems require latest Apple updates. Plug and play. Supports hot swapping. Backwards compatible with all USB 2.0/1.1 devices and hosts. Bus Powered - does not require an AC adapter - compatible with Microsoft Surface, Ultrabooks and MacBook Air The connection cable is attached to the hub -no need to worry about leaving it behind or losing it.