This compact device uses a ceramic element (small knob on surface of device pictured left) to pickup and amplify vibrations off any solid surface. With unsurpassed clarity and amplification, the Contact Microphone is an effective unit for testing audio leakage as well as probing for hidden devices. Excellent for listening in or through small boxes, sheetrock walls, and hardwood floors. The manufacturer packages the Contact Microphone as an experimental/training bomb detector and should be used for no other purpose |