Approved electronic whistle complete with loudspeaker, built-in membrane control panel and electronic controller. New ultrasonic heating system for improved acoustic membrane performance. Meets COLREG 1972 IMO class IV international regulations with RINA, LLOYD'S REGISTER MCA, BUREAU VERITAS, NMMA and BSH homologations. Includes mounting kit. Technical details: Voltage - 12 V, Consumption - 3 A, Frequency - 675 Hz, Volume - 122 dB, Dimensions - Ø 239 x 250 x 260 mm. For vessels of 12 to 20 m.