The RJ9W is a type of signal transmission cable used by Ninigi, a Japanese electronics maker. It is a 9-pin signal connector commonly used for the serial connection between a variety of devices such as modems, fax machines, printers, and more. The RJ9W is also referred to as a 9-pin modular connector, and is designed for quick setup and convenience. It features a quick release latching system, as well as a "solid core" strain relief that helps protect against accidental disconnects. The RJ9W is a reliable and efficient way to transmit signals.