Tips for buyers: * 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 expanded, so it has a certain possibility of produce howling after power-on. At present, small hearing aids and high-power hearing aids on the market can hardly avoid howling, and only full-digital hearing aids can avoid howling. Ways to avoid howling/noise: 1. When the power is high (the amplified sound is large), howling is more likely to occur. Therefore, gradually increasing the volume from low can effectively avoid howling. 2. When the ear canal is completely sealed, there is no howling sound. Therefore, please use hearing aids after cleaning your ear canal, and test the earplugs from large to small to find the most suitable earplugs. 3. After the hearing aid enters the ear canal, it is recommended to push the hearing aid with your fingers and hold it for 1-2 seconds, and then release it to fully extend the earplug. Instructions 1. Clean the ear canal before use. 2. When using it for the first time, please turn the volume to the minimum and then slowly increase it. 3. 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. 4. If the earbuds cannot fill the ear canal, it may cause feedback or whistler,So repeat step 3 to reduce howling and noise. Kindly Remind 1.Adjust volume to the minimum before wearing. 2.Increase volume gradually to avoid sudden increase in sound. 3.If you hear a howling, check the ear (silica gel) is appropriate and whether the size of plug is tight,the appropriate choice of earplugs and plugged, make sure no air leakage. 4.Keep the ear plug clean. 5.Turn off the hearing aid if you don't use it. Package included 1 x Hearing aid