This Listen by way of the Wall Device could present vital evidence for any private detective and private investigator as it can choose up even minute sounds, by way of a special amplifier, through walls, windows or partitions. Attached to the amplifier is actually a highly sensitive ceramic microphone which is designed to choose up vibrations that are converted into a voltage which could be then be created into audible sound. The amplifier has an adjustment to allow the sounds to be heard clearly and in the necessary volume.
Private detectives and private investigators can basically hold the device to the surface in question, up to 300mm thick, after which listen in via stereo headphones. All the evidence could be recorded by connecting a recording device, such as an MP3 player, into an audio output socket. A 9 volt battery powers the listen through the wall device and will give private detectives and private investigators as much as 24 hours of use. This really is surely a really helpful piece of kit for every private detective and private investigator.
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