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. If you hear a howling, check the ear (silica gel) is appropriate and whether the size of plug is tight, the appropriate choice of earplugs and plugged, make sure no air leakage. Keep the ear plug clean Remove the battery if you don't use it for long time.
Bluetooth Shape hearing aid Max Sound Output: 129dB ± 4dB Max Sound Gain: 55dB ± 5dB Harmonic Wave Distortion: ≤5% Frequency Range: 250~3800 hz Input Noise: ≤30 dB Battery: AG13 button cell battery (Not included) Working Voltage: dc1.5V Working Current: ≤4mA Color: As the picture shows. Item Size: 6.75 x 4.35 x 1.9cm Package Size: 9.6 x 8.2 x 3.4cm Net Weight: 10g
1 x AXON V183 In-Ear Hear Hearing Aid Sound Enhancer Assistance