# STC SA2685SO

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Quiet Technology Venture, Ltd, United States
- Description: Installation of Hush Kits. (707-300B ADVANCED)
- Status date: December 22, 1989
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 4A26](https://openairdocs.org/tcds/4A26)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/6FEA8F0D4716ACEA85256CC20008C750.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA2685SO

## ADs that name it (0)

None.

## Approved models (2)

- The Boeing Company 707-300B ([TCDS 4A26](https://openairdocs.org/tcds/4A26))
- The Boeing Company 707-300C ([TCDS 4A26](https://openairdocs.org/tcds/4A26))

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