1. Material: ABS
2. USB charging port
3. Lightweight and comfortable to wear
4. Built-in lithium battery 40mAh
5. Working current: less than or equal to 3mA
6. Working voltage: 1.2V
7. Working time: about 15 hours
8. Frequency range: 200-4000Hz
9. Input noise: less than or equal to 32dB
10. Output power: 3.6mW
11. Total harmonic distortion: less than or equal to 10%
12. Sound output: 125±4dB
13. Sound gain: 30±5dB
14. Net weight: 8g
15. Dimensions: 44x16x10mm