1. [Multiple application] High-strength through-wall microphone can be used for leakage on the pipe side, floor heating detection and water detection. Applicable to various piping materials and floors, walls, etc. 2. [Multifunctional] The wall microphone amplifier is fully functional with charging hole, headphone opening and on/off button to allow accurate measurement. Highly sensitive metal arrangement improves sensitivity and sound quality. 3. [Clear Sound] The voice hearing detector has excellent sound clarity and can be used anywhere, even indoors or in buildings. Built-in 200mAh lithium battery, compact design, easy to carry. Specification: Item Type: Through-wall microphone Material: plastic, electronic components. Product size: approx. 61 x 3.5 mm / 2.4 x 0.1 inches. Power Consumption: 10mA Battery: 200 mAh lithium battery (included). Operating temperature: -20℃-50℃. Applicable: cement wall B. steel wall, wood wall, iron wall, glass wall, hollow brick, etc. and various pipeline materials and floors, walls, etc. Monitoring method: headphones, external speakers can be connected Use: Use after charging. Package list: 1 x wall passage microphone. 1 x headphones. 1 x data cable. Note: 1. Manual measurement, please allow some errors.2. This detector is a simple home version and its sensitivity cannot be compared to more expensive products. It can only be tested briefly and must be purchased with caution for higher requirements.