---
kind: "section"
citation: "21 C.F.R. § 874.3330"
title: "21"
number: "874.3330"
heading: "Master hearing aid."
url: "https://uscodex.org/cfr/21/874.3330"
---

# §874.3330. Master hearing aid.

- (a) **Identification.** A master hearing aid is an electronic device intended to simulate a hearing aid during audiometric testing. It has adjustable acoustic output levels, such as those for gain, output, and frequency response. The device is used to select and adjust a person's wearable hearing aid.
- (b) **Classification.** Class II (special controls). The device is exempt from the premarket notification procedures in [subpart E of part 807](/cfr/21/part807-subpartE.md) of this chapter subject to the limitations in [§ 874.9](/cfr/21/874.9.md).

## Notes

### Amendments

[51 FR 40389, Nov. 6, 1986, as amended at 84 FR 71813, Dec. 30, 2019]

### Authority

Authority: 21 U.S.C. 351, 360, 360c, 360e, 360j, 360 l, 371.

### Source

Source: 51 FR 40389, Nov. 6, 1986, unless otherwise noted.

### Amendments

[51 FR 40389, Nov. 6, 1986, as amended at 84 FR 71813, Dec. 30, 2019]