Best Sound Amplifier Adjustable Tone Hearing Aids Aid Features: 100% brand new sound amplifier Super mini size and light weight, not easily to be seen Adjust volume to the minimum before wearing Increase volume gradually to avoid sudden increase in sound Powered by 2 x AG5 button cell battery (included) Size (without earplug): 2.1 x 1.6 cm (L X W) Color: as pictured Technical Specifications: Max Saturated Sound Pressure: 110dB+5dB Sound gain: ≥ 30db Harmonic Wave Distortion:≤ 10% Frequency response Range: 300--- 4000 Hz Input Noise: ≤ 40 dB Power Voltage :1.5 V Working Current : ≤4mA Battery Type: AG13 button cell battery (included) Package included: 1 x hearing aid amplifier 4 x earplug (different size) 4 x AG5 button cell battery 1 x manual 1 x case