Product Description SMART SENSOR Metal Detector is an electronic instrument which detects the presence of metal nearby. Metal detectors are useful for finding metal inclusions hidden within objects, or metal objects buried underground.?Nowadays, hand held metal detectors have become an important item from the point of view of security operations and procedures. Detection indication: Alarm buzzer/vibration/ear phone Detection size: 5*5*1 mm / Signal Frequency: 13kHz Object detection: aluminum, copper, iron & rare metals Sensitivity adjustable: Yes Power: 9V li-on Rechargeable Battery with charger Earphone jack: yes