Check the listing for details. New External Speaker Rectangular 3.5mm Plug Car Radio Speaker For Ham Radio CB. Condition: Open box. Listed at 19.99 USD. This high-quality external speaker is perfect for your car radio or ham radio CB. With a rectangular shape and 3.5mm plug connectivity, it provides crystal-clear sound for all your communication needs. The TRD550 model is designed to fit seamlessly into your setup, ensuring that you can use it with ease. Whether you're a professional truck driver or a hobbyist, this speaker is a must-have for clear and efficient communication. It's compatible with a wide range of devices, making it a versatile choice for anyone in need of a reliable speaker. So why wait? Upgrade your setup today with this top-of-the-line external speaker.