Industrial Covert Unlimited is in its 20th year of operation. CU1.COM has been up since mid 1999. Great security & CCTV products and people who answer the phone!
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ETS SMI-3 2 Zone Audio Surveillance Kit W/ 2 SM1 Microphones and SMI-2 Interface
The ETS SMI-3 is a 2 zone audio surveillance kit designed to connect to audio recorders, CCTV monitors (with built in speakers), video recorders, DVRs, remote monitoring equipment, etc.