Specification: 100% brand new sound amplifier behind the ear Super mini size and light weight, not easily to be seen Adjust volume to the minimum before wearing Choose an earplug of slightly bigger size to avoid whistler Increase volume gradually to avoid sudden increase in sound Technical Specifications: Max Saturated Sound Pressure: 130dB+5dB Harmonic Wave Distortion:≤ 5% Frequency response Range: 300--- 4000 Hz Input Noise: ≤ 30 dB Power Voltage :1.5 V
Working Current : ≤4mA Battery Type: AG13 button cell battery (included)