Table 1.
Summary of the characteristics of the ten OTC hearing aids.
| Models | Style | Cost ($US) | Country of manufacturer | Volume range | Special features | Operation manual | Technical specification | Battery | |
|---|---|---|---|---|---|---|---|---|---|
| A | LingYin HA 611B | BW | 41 | China | 1–5 | 2 tone controls (N; H) | Yes (Chinese) | Yes | AAA |
| B | Hopewell HAP-40 | BW | 22 | Unknown | No marking | — | Yes (English and Spanish) | No | AAA |
| C | Axwa EX-12D | BW | 49 | China | 1–8 | 3 tone controls (N; H; L) | Yes (English) | Yes | AA |
| D | JNC-MHA-BTE130 | BTE | 47 | Korea | 1–3 | — | Yes (Chinese and English) | Yes | 675 |
| E | UP-6411 | BTE | 52 | Japan# | 1–6 | — | Yes (English) | Yes | 675 |
| F | ShengDe V-163 | BTE | 51 | China | 1–4 | — | Yes (Chinese) | Yes | 675 |
| G | Axwa OM-188 | BTE | 55 | China | 1–4 | — | Yes (English) | Yes | 675 |
| H | Powertone HAP-F883 | ITE | 114 | Unknown | 1–5 | — | Yes (English) | Yes | 13 |
| I | JNC-MHA-ITE 110 | ITE | 47 | Korea | No marking | — | Yes (Chinese and English) | Yes | 312 |
| J | Axon K-80 | ITE | 37 | Unknown | No marking | — | Yes (English) | Yes | 312 |
Note. #: no information of manufacturer is printed on packaging, but the salesperson claimed that it was a Japanese brand; BW: body-worn; BTE: behind-the-ear; ITE: in-the-ear; N: normal; H: high; L: low; technical specification: manufacturer's information on electroacoustic characteristics of the hearing aid.