The FOS mono enables you to listen and record through concrete walls, windows, and doors without the need to be inside the room. The FOS is ideal for permanent installations in structures and walls, due to its light weight and waterproof design.

The FOS mono system is comprised of advanced fiber optic contact microphone & single-channel electro-optic unit (EOU200), for digital-to-analog conversion of optical microphone output signals. The Single Channel EOU 200 with enhanced electronics box. It features two analog outputs (one with volume control for headphones, another with fixed gain for monitor equipment); one pair of ST-style fiber optic connectors; two 3.5 mm sockets (one for analog output, another for headphones); green/red LED voltage indicator. DSP model provides up to 22 dB of real-time ambient noise removal (three levels: low, mid, high). Unit is powered either by internal battery or external DC power supply.