2012 Cheap heairng aid from factory F-139 1.Sound gain of 50dB 2.Easy use,invisible 3. ... ,Fast delivery 2012 Cheap heairng aid from factory F-139F-139 is a small BTE hearing aid,it's confortable for ... machine of Fonix 6500-C,,Fonix 7000 and CR6128Model:F-139 BTE Hearing AidMax Sound Output:129dB ± 4dBMax Sound Gain:50dB ... .1kgsGW per Carton22kgs 2012 Cheap heairng aid from factory F-139