Feature 1. Max sound gain:46±5,Suitable for mild to moderate hearing loss (Reference hearing loss map) 2. Binaural universal design.High power, louder. 3. Charging time: Charging 3 hours,can last about 10 hours.Saves your trouble to buy button batteries frequently. 4. If the ear dome is not completely fill into ear canal or air leaks at the ear dome, which will causes a annoying whistle.We give 3 different sizes of earplugs to reduce howling and noise. .
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