Feature:1. It can be used for pipeline side leakage / floor heating detection / physical exploration for water, suitable for various pipeline materials and ground, wall, etc.2. High-sensitivity metal probe with earphones makes it more sensitive and sound-qualified.3. Compact and complete function, with charging hole, earphone hole and upside switch knob.4. Easy to operate, it can get the sound out from the wooden/brick wall, window, door or armor plate.5. It has a built-in lithium battery, easy to operate and carry.Specification:Condition: 100% NewItem Type: Ear Listening DeviceMaterial: ABSColor: As Pictures ShownBuilt-in Battery Capacity: 200MAHSize: Approx. 42 x 37mm / 1.7 x 1.5in (Length x Diameter).Package List:1 x Ear Listening Device1 x Earphone1 x USB CableNote:The probe must contact the tube surface steadily. Please do not move the main unit in parallel during the contact to avoid damage to the instrument.