â Analogue BTE
â Volume control
â ON/OFF Switch
Max Sound Output: 129dB ± 4dB
Max Sound Gain: 50dB ± 5dB
Harmonic Wave Distortion: â¤5%
Frequency Range: 450~3500 hz
Input Noise: â¤30 dB
Battery: AG13
Working Voltage dc1.5V
Working Current: â¤4mA