Feature:1. Sound Sensitivity: Align with the high sensitivity metal of the earphone to improve sensitivity and sound quality. More convenient use experience.2. Powerful Function: The function is compact and complete, with charging hole, earphone hole and up switch knob. Humanized design, easy to use and adjust.3. Excellent Sound Clarity: It can be used anywhere, even indoors or in buildings, and has a built in lithium battery, which is easy to operate and carry.4. Easy to Operate: The sound can be made of wood coaxial, window, door or armor plate. Has good compatibility.5. Wide Application Range: It can be used for pipeline side leakage/floor heating detection/water body detection. Suitable for all kinds of pipeline materials, ground, pipelines, etc.Specification:Item Type: Sound AmplifierMaterial: ABSColour: BlackBattery: Lithium Battery (Included)Battery Capacity: 200mAParameters: Widely Used Sound Reinforcement Device, Suitable for Various Positions.Package List:1 x Sound Amplifier1 x Headphone1 x Micro SUB Power Supply Line