Dostyle Super Security Scanner, Hand Held Metal Detectors with 16 LED Metal Indicator lights and Adjustable Sensitivity With 16 LED Metal indication Lights : Indicator lights gradually change from green to red while detecting metal objects of different sizes. Two alternative alert ways: with a power switch to choose between Audio and Vibration, easy and convenient to operate. Adjustable Sensitivity Level: Low sensitivity switch, easily switch the sensitivity, realizing the detection of bulky goods and very small metal objects. Power supply is one 9V battery (Included). With one external charging jack, you also can fully charge it with a rechargeable battery (not included). Fast detecting speed and high sensitivity: Can detect a hand gun from 7.87 inches away, a dagger from 9.84 inches away, a 0.97in Diameter steel ball from 4.72 inches away.