SIIG 4-Port USB 3.0 Bay Hub via 20pin Header Add four front accessible SuperSpeed USB 3.0 ports to your desktop PC Installs in any 3.5" computer front bay or 5.25 with an optional adapter (SIIG part # AC-DB0011-S1) purchase separately Connects with system via internal 20pin USB 3.0 header Supports ultra-fast USB 3.0 data transfer rate of 5Gb/s and backward compatible with USB 2.0 and USB 1.1 devices Supports simultaneous operation of multiple USB 3.0, 2.0 and 1.1 devices Hot-swapping feature allows you to attach/detach devices without first powering your system off Works with high-bandwidth USB 3.0 devices, such as external hard disks, camcorders, high resolution webcams, cameras, multi-channel audio and more Supports UASP function (with Windows 8 native USB 3.0 Host driver only)