【Easy Operation with Smart Auto ON/OFF Function】This hearing amplifier automatically turns on 8 seconds after being taken out of the charging case and placed in the ear. After use, simply return it to the case to automatically turn it off and start charging. The green LED lights up while the hearing amplifier is charging and turns off when fully charged. The remaining charge of the charging case is clearly visible with a blue digital display. No complicated operations are required, providing a simple and intuitive user experience. *Please be careful not to cover the microphone hole when using (to prevent howling). 【Please Read Before Purchasing】Regarding the characteristics of hearing amplifiers, "selective amplification" is not possible, so not only conversational voices but also environmental sounds (vehicle noise/wind noise/everyday sounds, etc.) will be amplified. Please use it in a quiet room. This characteristic is a common structural feature of all hearing amplifiers. 【One-Touch Volume Adjustment, Up to 40dB Amplification】You can adjust the volume in 4 levels by simply pressing the volume adjustment button, and you can check the current volume level by the number of beeps. It is designed for easy operation even for the elderly. Equipped with a high-sensitivity noise-canceling chip, it reduces noise while amplifying sound up to 40dB, freeing you from the difficulty of hearing loud TV sounds and conversations with family, and improving your quality of life. Designed for those with mild to moderate hearing loss. 【Rechargeable and No Battery Replacement Needed】With a full charge, this rechargeable hearing amplifier can be used continuously for 20-30 hours, supporting your hearing for a full day on a single charge. The included 300mAh charging case allows for an amazing 100 hours of additional charging, and the remaining charge is clearly visible with the remaining charge display function (blue numbers indicate the remaining charge of the charging case)! Connect the charger and charging case with the included Type-C charging cable to charge the charging case. The number on the right will flash while charging, and charging is complete when it reaches '100'. 【Ultra-Lightweight at Just 3.2g for Comfortable Wear】Achieving a lightness that makes you forget it's there, your ears won't get tired even after wearing it all day. There is no distinction between left and right, so you can put it on either ear immediately, and you can take it out and use it right away even on busy mornings. The light and stylish design allows you to use it without hesitation when you're out and about. *Note: It may not fit those with particularly small ear canals.