Electric signal horn for 12-20 m vessels, supplemented by a loudspeaker, built-in membrane control panel and electronic controller, for 20-75 m vessels. New ultrasonic heating system provides improved acoustic membrane performance. MKL type approval, meets the international regulations of COLREG 1972 IMO Class IV and is in accordance with the classifications of RINA, LLOYD'S REGISTER MCA, BUREAU VERITAS, NMMA and BSH. Includes mounting kit. Material polycarbonate. Sound volume 122 dB/690 Hz. Automatic fog signal.