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
