Testing Item / Hearing Aid 
Weight ≤12 g
Rated Operational Voltage 1.5V
Rated Operational Current ≤8mA
Frequency response More than 450-3500 Hz
Equivalent input noise ≤32dB
Harmonic distortion f＜1000Hz ≤15%
f≥1000Hz ≤10%
Acoustic gain of full profile F=1600Hz 45±5dB                                                                   Power:1.5V/AG13(button cell)