The d link dub h4 20 is a hi speed universal serial bus 20 4 port hub with backward compatibility to usb 10 and 11 it provides an out of the box industry standard that allows connection of up to four usb peripherals or devices to your usb ready pc or mac the d link dub h4 is targeted at pc and mac users that are expanding the number of usb ports on their system the d link dub h4 20 is designed to provide quick and easy access to the four type quotaquot downstream ports for connecting usb per