Digital Hearing Aid K-82 In Ear Adjustable Hearing Device Sound Voice Amplifier Mini Pocket  Audiphone Hear Clear

About Whistle , you can do this 3 steps to remove it.

1. Choose a suitable earplug to make the product sealed in the ear canal

2. Low down the sound volume

3. When you put into battery , please be quick , to put the product into the ear

Note:

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.

Keep the ear plug clean

Remove the battery if you don't use it for long time.

If you don't know how to solv it, please contact the seller first

Features:

Combines a cosmetically appealing look with the smooth sound an internal speaker.
Filter out unwanted noise caused by airflow or wind Deliver direct, powerful, and smooth sound right into your ear.
Moisture resistant provides durability to most forms of moisture and wear.
Separate wire and headphone, more convenient and safety.
Provide improved technology for reduced electromagnetic interference.
Suitable for severe hearing loss people.
Smaller than a credit card, discreet enough to fit easily in your pocket or handbag.