The cause of howling/noise: The internal amplifier and the microphone are close to each other of the hearing aid, and the sound is continuously received and extended, so it has a certain possibility of producing howling after power-on.
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Input Noise:<=32dB. Max sound out put:118+/- 3dB. Sound gain:>= 35dB+/- 5dB. Main unit, Charging 2~3 hours for 20 hours use. Frequency range:300-4500MHz.
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Hearing aids can effectively reduce noise and amplify sound. Our accessories include earplugs of different sizes. This small device allows you to wear comfortably and provide a clear sound. |- [Comfortable] 360 degrees rotating connecting tube and ergonomic BTE design fit your ears.
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New and upgraded digital hearing aids. 1 x Hearing aids. Sound Gain: 38±5dB. 1 x USB line. Easy To Use: Easy to Operate For Seniors. 1 x Cleaning Brush. 1 x Gift box. 1 x User book.
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Features:-The volume can be easily adjusted with just a screw turn-Built-in energy-saving rechargeable battery prolongs battery life and extends the time between charges, supporting all-day use.-The charging box can be fully charged in 1.5hours, and after being fully charged, it can achieve an ultra-long standby time of 20 hours.-Each weighs only 3 grams, which is convenient and comfortable to wear. It comes with earplugs of different sizes to fit everyone's ears perfectly.-It adopts a compact and lightweight design, which satisfies your convenience of carrying and invisible wearing, and can be used anytime and anywhere.Specification:Colour: black&red&blueStyle: in the earPower source: built-in 300mAh batteryEquivalent input noise: 23dB ± .
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Features: -Specially designed for hearing-impaired people, more suitable for the ear canal. Even when used for a long time, there is no pain. -Your hearing aids can be charged using the detachable charging case (you will need to charge the charging case first). -Maximum gain is 117dB, suitable for moderate to severe hearing loss (see hearing loss table). -If the earmuffs are not fully inserted into the ear canal, or if the air leaks out of the earmuffs, it will cause an annoying whistling sound. We offer 3 different sizes of ear tips to reduce whistling and noise. -Super-mini size and light weight for easy carrying. .
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Insert the hearing aid into the ear canal,adjust its position in the ear canal until the soft eartip is fully deployed and fill the ear canal. Clean the ear canal before use. Turn off the hearing aid if you don't use it.
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This Powertone F-138 In-Ear Hearing Aid is a quality hearing aid which can help you hear the sound clearly and loudly. - Silicone ear pads in 3 different sizes, suitable for any form of ear. - If you hear a howling,check the ear (silicagel) is appropriate and whether the size of plug is tight, the appropriate choice of earplugs and plugged, make sure no air leakage.
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