Wall Listening Device

The amplification level can be increased by a dial located at the back of the device. You can listen to all those gossips and murmurs by increasing the amplification level. Now your ears can sneak in to the happenings behind the walls!Technically speaking the device is pretty simple. It works by amplifying the vibration of audio. Whenever you talk, the voices that are generated are wavebands, these wavebands travel through short and long distance.