1. Material: ABS
2. USB charging port
3. Lightweight and comfortable to wear
4. Built-in lithium battery 30mAh
5. Charging time: about 2 hours
6. Working voltage: d.c.1.2V
7. Working time: about 40 hours
8. Frequency range: 500-5000MHz
9. Input noise: less than or equal to 32dB
10. Working current: less than or equal to 1.2mA
11. Total harmonic distortion: less than or equal to 10%
12. Sound output: 129±3dB
13. Sound gain: greater than or equal to 40dB±5dB
14. Net weight: 6g