Description:What kind of people is it suitable for?It is the best choice for the elderly and people with mild and moderate hearing loss.Is there a harsh sound?If the hearing aid makes a harsh sound, it is caused by the wrong earplug size or the wrong wearing method.Please fit the hearing aid tightly into your ear canal. Otherwise, there will be airflow to produce a screaming sound!No sound/cannot turn on/unclear soundIf there are any problems during use, please let us know through Ebay. Our professional after-sales staff will solve it for you within 24 hours.How to use this hearing aid?1.Please fully charge before first use. Tear off the plastic sticker on the earphone before charging2.Insert the hearing aid tightly into the ear canal3.The hearing aid will d.