Origin:China MainlandModel Number:1607 Digital Hearing Aid Battery:Rechargeable Certification:CE Hearing Aids:Hearing Aid Listening Device:Elderly Deafness Earphones:Mini rechargeable Sound amplifier:RE-Sound Hearing Amplifier:Ear Care Severe Loss:Moderate loss Noise reduction:Amplifier Headphone amplifier:High quality hearing aids Volume contorl:Hearing aids Headphones:Sound Amplifier Rechargeable Hearing Aids:Severe Hearing Loss Earbuds Wireless:Low-Noise Powerful Hearing Aid:Deaf Headphones Digital Hearing Aid:Adjustable Tone Hearing Aids audifonos para sordera:aparatos auditivos Mini invisible hearing aid:Rechargeable hearing aids Digital Hearing Aids Rechargeable Hearing Aid Wireless Ear Aids audifonos Sound Amplifier for Deafness Elderly Hearing Aid to Severe Hearing Loss Support Dropshipping and Wholesale.We have RU warehouse. Buy more will get more discount, shipped within 24 hours! Product Feature 1.Mini size--Invisible to wear 2. Easy to operate for elderly 3. Digital chips, Noise reduction-Greatly reduce noise, providing high clear sound quality. 4. USB Rechargeable--no need to replace battery,use anytime,anywhere 5. Around 30 Hours to use after fully charged 6.Comfortable Listening Product Parameters: Size: 21.7x15x21.9mm Working voltage: DC 3.7V +5%, -10% Working current: 1.4mA Frequency response: 300-5000 Hz Equivalent Input Noise: 29dB, +3dB Maximum Saturation Acoustic Output: 128dB, +3dB Packing List: Ways to avoid Whistling /noise: Whistling is common for small amplifiers and is known as "Feedback".it is caused by amplified sound from the hearing aid getting back to the micropphone and being re-amplified.The folloring tips will help reduce the occurrence of feedback whistle: 1. Reduce the volume. Turn off or lower the volume before inserting the instrument in your ear.After inserting the ear,Increase volume gradually to avoid sudden increase in sound; 2. Securely position the instrument into your ear. Once the hearing aid is properly seated in your ear,the whistling will generally stop. 3. Clear the ear canal of wax or debris. Check your ear with help. 4. Change the ear piece or tubing Change a new one or a different size one.the appropriate choice of earplugs and plugged,Make sure the tubing is not broken or torn. Warranty and Feedback: 1)Item warranty:We provides a limited quality warranty of 12 months for the items sold dating. 2)If your items are defective(not due to misuse or wrong operation).please contact us within 7days be describing the defects in detail(if convenient and necessary,please send us photos or video clips for the faults of the defective items).We will have our engineers to analyze the faults and then tell what actions need to be taken for resolving the problem. If you are satisfied with the project, please give us a positive feedback. If you are not satisfied with the project, please contact us before leaving feedback. Please do not open dispute or leave negative feedback without talking to us, we will reply to all our customers and solve the problem you have met. Best regard !