The WS-420 Equalizer is a state of the art equalizer designed to provide amazing control and flexibility of your marine audio system. The WS-420 gives you independent control of your tower speakers as well as independent control of your in boat speakers. The Wet Sounds talk back microphone allows the boat driver to communicate with the rider or other boats in the area. By pushing the button on the microphone, the system will automatically mute the music playing from the tower speakers and allow you to use your tower speakers as a PA system. Once the button is released, the tower speakers will begin to play again at the level they were at. Additionally, the WS-420 includes Wet Sounds exclusive Boat Link™. Boat Link gives you the ability to link up with other WS-420 equipped boats for the ultimate party cove experience.