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ETS SMM4 4 Channel Microphone Mixer W/ 12VDC, Circuit Protection, and Easy Termination
The ETS SMM4 powers and mixes the audio of 4 microphones into one un-balanced line level RCA (or 3.5mm) output. Use to expand the coverage of one zone using up to 4 microphones or monitor up to 4 separate zones mixed together.
This is a perfect product for use in audio surveillance systems that have limited resources. The ETS SMM4 will work with all of the ETS microphones and most other microphones available for audio surveillance.