Description: 【High Sensitivity】: High sensitivity detection of sound from walls, windows, doors panels, with headphones included for clear sound quality. 【Wide Application】: Water leakage detection used for pipeline side leakage, floor heating detection, water body exploration. Suitable for many kinds of pipelines and ground. 【Powerful Function】: Water pipe leakage monitor equipped with charging hole, earphone hole and upward switch knob, easy to adjust. 【Easy to Use】: Through wall microphone is simple operation, close to the door, window, wall, adjust the volume until you hear a crisp sound. 【Note】:This Voice listen Tester is a simple family version, It can only be tested briefly. Specification: Material: ABS electronic components Size: 61x35mm/2.4x1.38in Current consumption: 10mA Battery capacity: 80-90mA Use battery: 9V  Working temperature: -20°-50° Suitable: Cement wall, steel wall, wooden wall, iron wall, glass, cavity brick monitor method: Earphone, Can be an external speaker Package Includes:(2 Pack) 1  Water Leakage Detection 1  Headphone 1 Cable 1 Probe