Metal detector utilizing electromagnetic induction principle, the use of alternating current through a coil to produce a rapidly changing magnetic field. The magnetic field inside the metal object can be an eddy current can be induced. Eddy current will produce a magnetic field, the magnetic field affect the original upside down, causing the detector beeps. 

Technical Parameters :

- Probe tips: Sound / Vibration 

- Detectable distance: 2.5inch/50mm

- Detection frequency: 13khz 

- LED light alarm 

- Sound alarm: > 75dB 

- Low battery indication function 

- Detection principle of electromagnetic induction 

- Can detect both positive and negative direction 

- There Lanyard 

- Working Environment: 0 ~ 40

- Storage temperature: -20 ~ 70  

Packing :

- 9V DC battery power 

- Product Weight: 365g 

- Product size: 410 * 80 * 40mm 

- Packing boxed