This item is specialy designed for rapid increase 7 USB3.0 ports to your computer with the high speed USB3.0.Its fine texture and compact appearance makes it suitable for different occasions.It integrated battery charge controller circuit, no external power supply can be easily extended to four USB3.0 interface.Bus-power limit current protection: 900mA.System requirements: windows XP, vista, win7, Mac OS (10.X or above) 7 Downstream(USB 3.0 A-type) Ports and 1 Upstream port.Compliant with USB version:1.1/2.0/3.0.Supports High-Speed(5G Mbps), Full-speed(480Mbps) and Low-speed(12Mbps) per-port Over-Curret detection and protection (when power adaptor connected) Supplies USB bus power(when power adaptor connected). Automatic switching between self-powered and bus-powered mode Supports Plug & PlayEach Hub With ON/OFF Switch,Easy To Control