Compatible with - Any 100 - 200 Watt Siren System. If the original speaker is 4 ohms. Using this 12V DC/8 Ohm speaker will result in a lower sound or not be able to produce sound. Super loud - This High Performance PA Siren Horn Speaker has a sound compression level of 125-135dB, 200 Watts, Impedance: 8 Ohms and a frequency range of 400-4000Hz.
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