Feature: 1. [Multi Application] High-strength through-wall microphone can be used for pipe-side leakage detection, floor heating inspection, and water detection. Applicable to various pipeline materials and surfaces such as floors, walls, etc. 2. [Multi Functional] Through-wall microphone amplifier features a charging port, headphone jack, and on/off knob for reliable operation and accurate sound detection. High-sensitivity metal construction enhances sensitivity and audio quality. 3. [Clear Sound] Voice listening detector delivers excellent sound clarity and can be used in various environments, including indoors or within buildings. Built-in 200mAh lithium battery, compact design for easy portability. 4. [Easy To Operate] The probe attaches to various piping materials, floors, and walls, allowing users to hear subtle sounds through the included earphone that are typically inaudible. 5. [Widely Used] Ear listening device amplifier is compatible with concrete walls, steel walls, wooden walls, iron walls, glass walls, hollow blocks, and various pipeline materials and surfaces to meet diverse detection needs. Specification: Item Type: Through Wall Microphone Material: Plastic, Electronic Components Product Size: Approx. 61 x 35mm / 2.4 x 1.4in Current Consumption: 10mA Battery: 200mAh Li Battery (Included) Operating Temperature: -20°C to 50°C Applicable Surfaces: Cement wall, steel wall, wooden wall, iron wall, glass wall, hollow bricks, and various piping materials, floors, walls, etc. Monitoring Method: Headphone output; external speakers can be connected. Package List: 1 x Through Wall Microphone 1 x Earphone 1 x Data Cable Note: 1. Manual measurement; please allow slight dimensional variations. 2. This detector is a basic home-use model and its sensitivity may not match that of higher-end professional equipment. It is intended for preliminary testing only and should be purchased with consideration of intended use.