With 30 watts of power, Raymarine's waterproof Ray 430 loud hailer gets another boat's undivided attention. In the fog, the Ray 430's eight foghorn signals warn other boats of your presence. In between hail and fog signals the Ray 430 automatically reverts to "Listen" mode so you can hear any oncoming boats, buoys, or distant cries for help, a reassuring safety feature when visibility is poor. Other features include an oversized LCD display, 4-station intercom hookup, and the capability to connect with alarm sensors for security. Unit measures: 5.3"H x 10.9"W x 4.0"D with bracket. Speaker not included.