Max Sound Output: 120dB
Max Sound Gain:≥30 dB
Harmonic Wave Distortion: ≤5%
Frequency Range: 300~4000 hz
Input Noise: ≤50 dB
Battery: AG3 Button battery
Max Working Hours with Standard Battery: 70 h
Working Voltage: D.C. 1.5V
Working Current: ≤4 mA
Net Weight: 9 g (without Battery)
Special Function Key: None