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ETS WS4 4" Wall Mount Speaker W/ Grill & 70V Transformer for Audio Surveillance
The ETS WS4 4" speaker is for use with remote monitoring two-way audio surveillance systems or public address systems. This speaker mounts to your wall and it uses a 70V transformer for your power needs.
So if you're looking for a speaker system to attach to your PA system or your audio surveillance kit; then the WS4 from ETS just might do the trick for you.