Powerful Audio Wiretap Listen Device Fold Ear Amplifier Wall Door Eavesdropping Surveillance with Earphone(Black) Next door wiretap the sound barrier-free multi-function filter: 1. Can be wood walls, walls, doors and windows, wall plates, such as voice. 2. The voice of the high-sensitivity detectors, so that you fully grasp the voices of the next room. 3. With headphones and audio output hole may be synchronized with the audio tape recorders in general, is to collect evidence Essential equipment. 4. Applies to business, reported the situation * check * card. The entire equipment including 1. The main equipment: volume is about the size of jelly, black, equipment upper charging jack, headphone jack, regulating switch stick, equipment acquisition at the bottom for the voice part (to be listening closely to the wall of the room, plate, doors, etc.). 2. High-definition stereo headphones. 3. Charging lines, packing box. Application method: After the device fully charged, plug in headphones, the sound equipment collected at the bottom close to the wall surface, open-conditioning equipment stick switch, turning stick until it heard a clear voice, the voice recorder can also use the headphone plug to connect equipment hole for a long period of recording..