Hearing Aids For Seniors Rechargeable Sound Amplifier for Deafne/Elderly Ear Care Hearing Amplifier Digital Sound Aid Wirele Earphones DropShip Information: 1.Product size: 43x15x10 mm 2.Weight:4 g 3.Max. saturation sound preure level(SSPL):130dB±4dB 4.Full on Acoustic Gain:F=1600Hz,45±5dB 5.Total Harmonic Distortion(THD):F>1000H 15% F<1000H 10% 6.Frequency Response:450-3500 Hz 7.Equivalent Input Noise:32 dB 8.Battery:Rechargeable 9.Battery Current Drain:4 mA 10.Estimated Battery Life:48 Hours 11.Rated Voltage:D.C 1.5V Packing list: Hearing Aid * 1 Charger * 1 Silicone earplugs * 3 Cleaning brush * 1 USB * 1 Manual * 1 it is comfortable for you to wear for long time. Lightweight-wearing it on the ears can hardly feel the existence. Chip-Level Noise Reduction, Intelligence Helps You Filter Out Noisy Noises, Giving You A Quiet World No Battery Anxiety Package list: Note: 1.Adjust volume to the minimum before wearing; 2.Choose an earplug of slightly bigger size to avoid whistler; 3.Increase volume gradually to avoid sudden increase in sound; 4.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; 5.Keep the ear plug clean; 6.Remove the battery if you don't use it for long time.