Motherboard COM Serial Backplane, 9DB Pin Backplane, Nine-Pin COM Serial Cable. Motherboard COM Serial Port Cable/Extension Port, Chicle Connector Wire/Nine-Pin COM Serial Cable. A header for the standard 9-pin COM interface. Additionally, a header from the motherboard, insert the pin. The backplane connects to the PCI slot on the back of the chassis. Lightweight and easy to install, add a 9-pin COM port to your computer. Product Description: 1. Used to extend the COM interface connected to the motherboard and the old game controller interface. You need this extension function for the motherboard to be usable. The cable length is approximately 30 cm. 2. COM connection cable with backplane. The cable is installed on the motherboard's serial port, allowing you to add a COM port to your computer. With the backplane installed on the PCI slot. Motherboard COM Serial Backplane, 9DB Pin Backplane, Nine-Pin COM Serial Cable. Motherboard COM Serial Port Cable/Extension Port, Chicle Connector Wire/Nine-Pin COM Serial Cable. 9-pin COM nozzle backplane. A header for the standard 9-pin COM interface. Additionally, a header from the motherboard, insert the pin. The backplane connects to the PCI slot on the back of the chassis. Lightweight and easy to install, add a 9-pin COM port to your computer.