RJ11 to USB：RJ11 6P4C Male to USB Female Phone Port Adapter Connector. Easy conversion between RJ11 telephone jack and USB A interface APPLICATION：RJ11 6P4C revolving USB A female telephone line connector. USB cables can be converted into RJ11 telephone lines for use in connecting phones, communications, fax machines, and modems LIGHTWEIGHT and COMPACT: RJ11 6P4C Male to USB2.0 Female Phone line connector. Compact and lightweight, easy to carry，making it an ideal solution for offices, homes, or on-site use. PLUG AND PLAY: Plug and play, no installation required RJ11 PORT TEST : RJ11 plug to USB socket Phone Port test adapter. Connects to computer via USB cable for RJ11 6P4C port testing This is a practical RJ11 to USB interface converter. It converts the traditional telephone line interface (RJ11 6P4C) into a universal USB interface, allowing your modern computer to easily connect and control old-fashioned fax machines, modems, or telephone devices, making it a powerful assistant for office communication and equipment maintenance