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ETS SM7va 4 Zone Audio/Video System W/ 4 SM1 Microphones & a SM4va Audio/Video Switcher
The ETS SM7va is a 4 zone, sequential or manual switching, audio/video surveillance system (cameras not supplied). This audio surveillance kit can be used independently for monitoring live audio / video or with digital recorders for recording and playback.
This kit has two modes of operation: Audio follow video mode or audio mixer / switcher operates independently of video switcher.
This audio surveillance kit includes 4 SM1 microphones as well as the SM4va audio / video switcher / mixer / amplifier.
Features of this kit include a 25' pickup radius from the microphone, adjustable gain, a treble boost circuit, and 12VDC power use. So if you're looking for a quality audio surveillance kit, then the SM7va may be perfect for your needs.