The Duobao SU-50B is a passive marine horn loudspeaker designed for shipboard applications. With a rated power of 50W, 8Ω impedance, and IP65 ingress protection, it delivers clear and loud audio signals for ship announcements, alarms, and siren signals in engine rooms, bridges, and open decks. Manufactured by Shanghai Duobao Electronics and CE certified, this speaker meets marine environmental requirements for durability and reliability.