Add gigabit ethernet network connectivity to a laptop or desktop through a usb 30 port the usb31000s usb 30 to gigabit ethernet adapter adds a single rj45 ethernet port to a usb enabled computer system with support for gigabit network connections at full bandwidth unlike usb 20 adapters this compact usb 30 network adapter is backward compatible with older usb 201x computer systems speed limited by usb bus making it the ideal portable replacement network adapter or laptop accesso