Stereo Listening Through Wall System

Description
This multi-function stereo listening through wall device is an updated product nowadays, which can give listener the clearest audio information they are going to know. This is a special amplifier that will pick up the slightest noise through solid objects like a wall, so you can listen to what is happening on the other side. The contact microphone is a ceramic pin specially developed for converting vibration into audible noise. It has two powerful transducers together comprise an exceptional monitoring device. It is widely used in police, prison and intelligence department.
Features
● High Detection sensitivity.
● The threshold frequency,gain of the amplifier and microphone are adjustable.
● The gain of the amplifier can be infinitely adjusted.
● People can monitor with channel 1, channel 2 separately or simultaneously.  
● Built-in recording function, it can record automatically when insert dedicated memory card.