Origin:China MainlandModel Number:VHP-1607 Certification:CE Hearing Aid Digital:Hearing aids Rechargeable Rechargeable Hearing Aids:Powerful Hearing Aid Mini Hearing Aid:Adjustable Tone Hearing Aids audifonos para sordera:Intelligent Noise Reduction Hearing Aids audifonos:Hearing Aids For Deafness Elderly Mini Hearing Aids Rechargeable Digital Hearing Aid Wireless Ear Aids Dropshipping Intelligent Noise Reduction Sound Amplifier for Deafness Elderly to Severe Hearing Loss . Feature 1.Mini size--Invisible to wear 2. Easy to operate for elderly 3. Digital chips, Noise reduction-Anti-howling,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 Parameter: 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 Package List: Tips for buyers: Ways to avoid howling/noise: Whistling may occur if the hearing instrument is turned on,but not securely seated in your ear.this is normal.the whistling will stop once the device is properly seated in your ear. 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. 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.