Overview: It can be used for public security in airports, railway stations, docks, prisons, customs & frontier defense as well as quality control of medicine, food & other commodities. With very low power consumption, this detector can work for over 40 hours continuously Beep sound, LED indicator or vibration when metal detected Control: circulation switch (ON, OFF, a sound of light or mode of vibration) Operating Frequency: 20 K Hz Adjustable sensitivity Operating power: 9V DC Battery (not included) Low battery alarm Specifications: Dimensions: 16.53 in x 5.43 in x 1.61 in Weight: 14.74