technical parameter: 1. Power control: button switch; long press for 1 second to switch the machine 2. Sound and light alarm, with 5-speed adjustment; with vibration and buzzer mode; can be used in noisy environments. 3. Tone identification: Using the ATD feature, when detecting a small metal target, the audio volume will change, and when detecting a large metal target, the audio volume and tone will change. 4. Low battery voltage indication: When the voltage is low, a continuous alarm sound is heard, the green READY light stops flashing, and the red ALERT light emits red light. Related parameters: 5. Working frequency: with automatic frequency conversion function, 25-95KHZ; 6. Working temperature: -20ºC-45ºC; 7. Alarm indication: speaker, LED traffic light; 8. Power battery : Built-in 1800mah mAh lithium battery; 9. Charging interface: USB Type C interface 5V1A 10. The red light flashes when charging, and turns green when fully charged 11. Energy-saving mode: built-in energy-saving module, automatically shut down when not used for 15 minutes 12. Dimensions: length 41cm*width 8.2cm*height 4.1cm 13. Product weight: net weight 360 grams