... usb hub, Expand for USB port,supply up to 500mA current per port, No external power supply USB Hub4 port usb hub, usb light, usb ... memory hub, hub, usb, usb card reader, usb flash drive, card ... 500mA current per port2)Adopt the second age USB controller3)No external power supply4)Driverless,hot plug and play5)Design ...