1.Output power: 3.6mW
2. Maximum sound output: 130 � 4dB
3. Sound gain: 30 dB
4. Frequency range: 100--4000 Hz
5.Equivalent input noise: ≤28dB
6.Harmonic distortion: ≤6%
7.Continuous working time: ≥15 hours
8.Battery capacity: 40 mA battery is rechargeable
9.Working current: ≤3 mA
10. Working voltage: 1.2V
2. Maximum sound output: 130 � 4dB
3. Sound gain: 30 dB
4. Frequency range: 100--4000 Hz
5.Equivalent input noise: ≤28dB
6.Harmonic distortion: ≤6%
7.Continuous working time: ≥15 hours
8.Battery capacity: 40 mA battery is rechargeable
9.Working current: ≤3 mA
10. Working voltage: 1.2V