【Noise Reduction & Excellent Sound 】This amplifier uses advanced microprocessor technology to achieve clear reception while reducing background noise. Provides good sound to help you hear clearly and loudly. Doctor-designed hearing aid with 35 dB gain, making this sound amplifier ideal for mild to moderate hearing loss.【Automatic Feedback & Adjustable Volume】Automatic feedback compression DFS system, monitors the howling frequency point and eliminates it immediately. Suitable for carrying mobile phones. Suitable for carrying mobile phones. It is designed with adjustable volume levels to suit your environment. Connect the earbuds to the machine, please make sure the earbuds are in close with the ear canal. Adjust the volume from the lowest to the est, after connecting the adapter, you can slowly adjust to the volume.【Ergonomic Design and Long-lasting Battery Use】Can be used for any ear. Lightweight and comfortable to wear. Easy to carry. No pain or swelling for long-term wear. Ultra-low background noise of the machine itself. One A10 battery lasts up to 600 hours, providing 75 days (8 hours a day) of use. Perfect for home use, movies, church restaurants, travel, etc.【Convenient and Easy to Use】Pre-installed, includes a convenient dry box and 4 silicone ear tips of different sizes to ensure the best fit. It can be easily operated with just your fingers. For the first time wearing, just adjust the volume to level 1-2. If you can't hear clearly, you can slowly increase the volume. We recommend that you wear it for 8 hours a day, and you will feel comfortable after 2-3 weeks.