Hearing Aid Sound Amplifier Aid for Deafness

MaxSound output: 130 ± 5 dB
Maximum sound gain: 55 +- 5 dB
Harmonic wave distortion: <= 10%(1000Hz)
Frequency: 300-4500Hz
Input noise: <= 30 dB
Battery: AG13 button cell (include 1pcs, due to post office forbid to send too much battery, we will send 1pcs battery for your reference.)
Working voltage: dc1.5V
Operating current: <= 0 3mA
Color: as shown in the picture
Item Size: 3.8x2.1x0.9x3cm

1. Adjust the volume to minimum before wearing it.
2. Choose an earplug one size larger to avoid whistling.
3. Increase the volume gradually to avoid a sudden increase in sound.
4. If you hear a howling sound, check the ear (silica gel) is suitable and whether the plug size is tight, the appropriate choice of earplugs and plugged in, make sure there is no air leakage.
5. Keep the earplug clean
6. Remove the battery if not used for a long time.