Specification:
Max sound output: 129dB ± 4dB
Max Sound Gain: 50dB ± 5dB
Harmonic Wave Distortion: ≤5%
Input Noise: ≤30 dB
Frequency Range: 350~3500 hz
Voltage: 1.5V
Current: ≤4 mA
Battery: 5# dry battery
Package included:
1 x hearing aid amplifier
4 x earplug (different size)
1 x manual
1 x case