Flammi Portable 4-Port USB 3.0 Hub with Independent Power Switches 4-port usb 3.0 hub without power adapter It is backward compatible with USB 2.0/1.1 Connect 5Gbps/480Mbps/12Mbps/1.5Mbps USB peripherals Suitable for notebook computer,PDA,laptop Hot-swappable, plug and play,don't need to install driver