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ETS SMI5 4 Zone Audio Surveillance Kit W/ SM1 Microphones, SMI4 Interface Box, and Accessories
The ETS SMI5 is a 4 zone audio surveillance system that is designed to connect directly to audio recorders, video recorders, CCTV monitors (with a built in speaker), remote monitoring equipment, and more.
This audio surveillance kit includes 4 of the SM1 microphones as well as the SMI4 interface box to allow the microphones to interface with a DVR or other recording equipment.
Features of this kit include a 25' pickup radius from the microphones, adjustable gain, a treble boost circuit, and 12VDC power use. So if you're looking for a quality audio surveillance kit, then the SMI5 may be perfect for your needs.