USB 3.0 Header to USB 2.0 Header Adapter Cable. 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). 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.
