The Uniden PRO505XL 40 Channel CB Radio is perfect for those long days on the road. It features an instant channel 9 function where you can quickly set the radio to the emergency/channel 9. You can check the relative strength of incoming transmissions with the signal/RF power indicator. This CB radio has an external speaker jack that will let you plug in an external speaker for better sound as well as an external PA jack that allows connection of a PA speaker. Other features include 40 channel operation, squelch control, channel display, volume control, mounting hardware, channel select buttons, and a large, easy-to-read display.