Luiwoon Diy Hy929 High Strength Wall Microphone Voice Listen Detecotor For Engineer Water Leakage Oil Leaki

Works on wooden walls, doors, windows, steel plates, etc. Highly Sensitive, carefully adjust audio slowly, as not to cause discomfort to your ear-buds This audio gadget works by amplifying the vibrations of audio. When people are talking in a room their voices are simply a waveband, and depending on how loud they are talking, the waveband travels short and long distances which are picked up and amplified by this device. colour:Black + Silver Material:metal Package Contents: 1* Detecotor 1* USB Cable 1* Circular probe 1* Needle probe 1* Headphone 1 * use Manual Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.