BTE Hearing Aid Ear for Deafness Sound Amplifier Adjustable Hearing Aids Portable Super Ear Hearing Amplifier for the Elderly. Hearing aid. 1 x JZ-1088A Hearing aid. 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.
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