Add four external usb 30 ports to your notebook or ultrabook with a slim portable hub the st4300minu3b portable 4 port superspeed mini usb 30 hub black lets you expand your usb connectivity by turning a single usb 30 port into four external usb 30 ports the integrated cable design makes this mini usb hub the perfect accessory for your mac pc notebook or ultrabook computer the 4 port usb 30 hub supports usb 30 data bandwidth 5 gbps up to 10x more than usb 20 and is backward