This Listen via the Wall Device could provide vital evidence for any private detective and private investigator as it can choose up even minute sounds, via a unique amplifier, by means of walls, windows or partitions. Attached to the amplifier is actually a very sensitive ceramic microphone which is developed to pick up vibrations that are converted into a voltage which can be then be made into audible sound. The amplifier has an adjustment to enable the sounds to be heard clearly and in the required volume.
Private detectives and private investigators can simply hold the device to the surface in question, as much as 300mm thick, and then listen in via stereo headphones. All of the evidence might be recorded by connecting a recording device, for example an MP3 player, into an audio output socket. A 9 volt battery powers the listen by means of the wall device and will give private detectives and private investigators up to 24 hours of use. This is surely a very helpful piece of kit for each and every private detective and private investigator.
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