1. Sound output (MAX): 129+/-4 dB
2. Sound Gain (MAX): 50dB +/- 5dB
3. Harmonic distortion: less than or equal to 5%
4. Frequency range: 450~3500hz
5. Input noise: less than or equal to 30 dB
6. Battery: Lithium battery
7. Working voltage: DC 3.7V
8. Working current: less than or equal to 3mA
9. Dimensions: 6.6 x 1.3 x 1.3cm
10. Net weight: 26g
11. Please do not use the computer to charge.
12. Please do not charge more than 6 hours