# STC SA4-891

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Winslow Aerofilter Corp, United States
- Description: Full flow oil filter 30409A with element 1A0235.
- Status date: January 1, 1960
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A18](https://openairdocs.org/tcds/3A18)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E4B98B87B66CD958862570D0007BA9E9.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA4-891

## ADs that name it (0)

None.

## Approved models (1)

- Prop-Jets Inc. 200 Series ([TCDS 3A18](https://openairdocs.org/tcds/3A18))

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