20 pin USB 3.0 male header (this is a 20-pin header). 9 pin USB 2.0 female header (this is a 9-pin header). USB 3.0 Header to USB 2.0 Header Adapter Cable. For USB 2.0 motherboard header. The cable can let the USB 3.0 20 pin device connected to the USB 2.0 motherboard, such as CD-ROM, floppy drive panel.
