Cobra 19 DX IV is a CB radio transceiver with 40 channels, including instant channels 9 and 19, and a public address (PA) system. It features a dynamic microphone with a 9-foot cord and a compact size for easy installation in vehicles. The RF gain control allows you to adjust the sensitivity of the receiver, and the squelch control helps eliminate background noise. The Cobra 19 DX IV also has a built-in S/RF power meter and a backlit LCD channel display.