... easy to install Marine Electric Whistle with MIC + audio amplifier 120W Size: 160*55*145mmType: 120WattDescription:an ... integrated device, containing MIC, whistle, audio qmplifier, Enlarge / diminish sound source.These products adopt ... Ω(5)Panel description: power switch / volume, microphone socket; audio amplifier button ; whistle button ; Item: Microphone Model No: ...