With the combo you can easily add 2xUSB3.0-Port Hub and 2xUSB2.0-Port Hub to your desktop， from its USB3.0&2.0 connector. 3.5" Floppy Bay 2 USB3.0 and 2 USB2.0 4Ports Hub USB3.0 20Pin connector for USB3.0 Hub USB2.0 connector for USB2.0 Hub Features: Come with 2 USB3.0 Hub and 2 USB2.0 Hub USB3.0 20Pin connector for USB3.0 Hub USB2.0 connector for USB2.0 Hub Material: industrial plastic anti-high-temperature and iron shell 2 USB3.0 ports & 2 USB2.0 ports-A female ports Data transfer rate up to 5Gbps Copper conductor for maximum conductivity and reliablity High density double shielding for maximum rejection of EMI and RFI Plug and play driver less installation Backward compatible with USB 2.0 and 1.1 Fits inside 3.5 inches open bay Support System: Windows， XP， Vista， Windows 7 8 32&64 Bit and Mac OS Plug&Play， no driver needed Note: the USB3.0 20Pin connector is actually 19pin， as one pin of the connector is blocked up. Specification: USB Cable: 60-70cm User manual: 1. Turn off your PC; 2. Install the Hub to PC 3. Connect the USB3.0 20Pin connector to your motherboard 4 Connect the USB2.0 connector to your PC 5. Turn on your PC and you can enjoy great speed. Package Includes: 1 x 3.5" USB Hub Floppy Bay Front Panel 4 x screws