As to those deaf people， hearing aid is of great significance. Our F-137 Professional Earplug Hearing Aid will be your regretless choice! Specially designed with advanced technology and meticulous workmanship， it provides enough precision and accuracy in sound reproduction. Simple elegant ergonomic design makes this hearing aid much comfortable to wear. What is more， you will hear speeches， concerts and presentations much better if youwear this item. Do not hesitate anymore! You will get a rebirth from this order!                                    Features            New and high qualityEasy to use and make voice louderHigh effective and reliable to useWhile in forest， if you want to hear very slight sound， it will be a good choiceReasonable price and good after sale serviceWith earplug design， it is convenient to carrySuitable for speeches， concerts and presentations                                                            Specifications             Max Sound Output     130±5dB    <br> Sound Gain     ≥50dB    <br> Toutal Harmonic Wave Distortion     ≤3%    <br> Frequency Range     300~4000Hz    <br> Input Noise     ≤30dB    <br> Voltage     DC 1.5V    <br> Current     ≤3mA    <br> Dimensions     (1.77 x 1.38 x 0.59)" / (4.5 x 3.5 x 1.5)cm (L x W x H)      <br> Weight     84g / 2.96oz      <br>                                                             Package Includes            1 x  Hearing Aid<br>2 x Battery<br>1 x User Manual<br>4 x Earplug<br>