Aeroquip Rynglok® to Permaswage® Cross-Reference Guide: Part Numbers, NSNs & Aerospace Fitting Identification
Identifying the correct aerospace tube fitting can be challenging, particularly when working with legacy aircraft systems, discontinued part numbers, military inventory records, or fittings manufactured under different product families.
Two well-known aerospace tube-connection systems are Aeroquip Rynglok® and Permaswage®. Historical Aeroquip documentation provides part-number cross-references between numerous Rynglok® and Permaswage® fitting families, along with National Stock Numbers (NSNs) assigned to individual Rynglok® fittings.
This guide provides a reference for aerospace procurement departments, maintenance technicians, MRO facilities, military supply organizations, and aircraft operators researching Rynglok® and Permaswage® fittings.
Important: The cross-references presented here are historical identification references. They do not independently establish current interchangeability, installation approval, or suitability for a particular aircraft application.
Understanding Rynglok® and Permaswage® Fittings
Rynglok® and Permaswage® are aerospace tube-fitting systems used in fluid-line applications. Both product families include permanent tube fittings and various adapter configurations.
Historical Aeroquip cross-reference documentation identifies corresponding fitting families for configurations such as:
- Straight unions
- Union reducers
- 45-degree elbows
- 90-degree elbows
- Elbow reducers
- Tee fittings
- Tee reducers
- Cross fittings
- Lipseal adapters
- Flareless adapters
- Flared adapters
- Bulkhead fittings
These references can help buyers identify related product families when researching legacy inventory or locating documentation for an unfamiliar part number.
Rynglok® to Permaswage® Permanent Fitting Cross-Reference
The following table reproduces the permanent-fitting family relationships recorded in the historical Aeroquip cross-reference.
| Fitting Configuration | Permaswage® P/N Family | Rynglok® P/N Family |
|---|---|---|
| Union | D10036 / D10136 | R80101T |
| Union Reducer | D10045 | R80151T |
| 45° Elbow | D10090 | R80102T |
| 90° Elbow | D9856 / D10256 | R80103T |
| 90° Elbow Reducer | D10035 / D10235 | R80153T |
| Tee | D9855 / D10255 | R80104T |
| Tee Reducer | D10023 / D10223 | R80154T |
| Cross | D9854 / D10254 | R80105T |
| Cross Reducer | D10033 | R80155T |
These are part-number family patterns rather than complete individual fitting part numbers. Size and port-configuration suffixes must be verified against the applicable manufacturer documentation.
Rynglok® to Permaswage® Adapter Cross-Reference
The historical reference also identifies relationships between several adapter fitting families.
| Fitting Configuration | Permaswage® Family | Rynglok® Family |
|---|---|---|
| Female Lipseal Straight Adapter | D11200 | R81101T |
| Female Lipseal 45° Elbow | D11055A | R81102T |
| Female Lipseal 90° Elbow | D11009 | R81103T |
| Flareless Swivel Nut 90° Elbow | D10021A | R82103T |
| Flareless Male Straight Adapter | D10008 | R82121T |
| Flareless Male 90° Elbow | D10034 | R82123T |
| Bulkhead Flareless Male Straight Adapter | D10019 | R82141T |
| Flared Swivel Nut 90° Elbow | D10027A | R83103T |
| Flared Male Straight Adapter | D10011 | R83121T |
These examples are a selection from the historical reference and do not represent every available adapter configuration.
What Is a National Stock Number (NSN)?
A National Stock Number is a standardized identification number used within military and government supply systems to identify an item of supply.
An NSN contains 13 digits. The first four identify the Federal Supply Classification, while the remaining nine constitute the National Item Identification Number.
For example, the historical Rynglok® fitting reference contains NSNs beginning with 4730, the Federal Supply Classification associated with hose, pipe, tube, lubrication, and railing fittings.
NSNs can help procurement personnel research legacy fittings, military inventory, supply records, and historical part-number relationships.
However, an NSN assigned to a Rynglok® fitting should not automatically be treated as an NSN assigned to a corresponding Permaswage® fitting.
Rynglok® Union Fittings — Part Number and NSN Reference
The following Rynglok® union fitting part numbers and NSNs are recorded in the historical Aeroquip NSN listing.
| Rynglok® P/N | NSN |
|---|---|
| R80101T03 | 4730-01-354-8993 |
| R80101T04 | 4730-01-355-0452 |
| R80101T05 | 4730-01-354-8994 |
| R80101T06 | 4730-01-354-8995 |
| R80101T08 | 4730-01-355-3245 |
| R80101T10 | 4730-01-355-3246 |
| R80101T12 | 4730-01-355-3247 |
| R80101T14 | 4730-01-355-3248 |
| R80101T16 | 4730-01-355-5901 |
| R80101T20 | 4730-01-367-7434 |
| R80101T24 | 4730-01-367-7435 |
The historical family cross-reference associates Rynglok® R80101T unions with the Permaswage® D10036 and D10136 union families. The applicable size, configuration, and individual part-number relationship must be verified before selecting a replacement.
Rynglok® 90° Elbow Fittings — Part Number and NSN Reference
The historical Rynglok® NSN listing also identifies the following permanent 90-degree elbow fittings.
| Rynglok® P/N | NSN |
|---|---|
| R80103T04 | 4730-01-392-2403 |
| R80103T06 | 4730-01-392-2395 |
| R80103T08 | 4730-01-392-2363 |
| R80103T10 | 4730-01-392-2357 |
| R80103T12 | 4730-01-392-2359 |
| R80103T14 | 4730-01-392-2360 |
| R80103T16 | 4730-01-392-2367 |
| R80103T20 | 4730-01-392-2368 |
The corresponding historical Permaswage® fitting families are D9856 and D10256.
Rynglok® Tee Fittings — Part Number and NSN Reference
| Rynglok® P/N | NSN |
|---|---|
| R80104T04 | 4730-01-392-3904 |
| R80104T06 | 4730-01-392-3905 |
| R80104T08 | 4730-01-392-3950 |
| R80104T10 | 4730-01-392-3899 |
| R80104T12 | 4730-01-392-3894 |
| R80104T14 | 4730-01-392-3895 |
| R80104T16 | 4730-01-392-3896 |
| R80104T20 | 4730-01-392-3897 |
The historical family cross-reference associates Rynglok® R80104T tee fittings with the Permaswage® D9855 and D10255 families.
How to Use a Rynglok® NSN to Research a Permaswage® Fitting
When researching an aircraft fitting using a National Stock Number, the recommended process is:
- Locate the NSN in the historical Rynglok® listing.
- Identify the Rynglok® manufacturer part number associated with that NSN.
- Locate the Rynglok® fitting family in the historical cross-reference.
- Identify the corresponding Permaswage® family or families.
- Verify the exact size, fitting configuration, material, pressure requirements, and part-number suffix.
- Confirm whether the proposed fitting is permitted by the applicable aircraft maintenance data, engineering authority, and procurement requirements.
For example, NSN 4730-01-355-3245 is listed against Rynglok® part number R80101T08. The historical cross-reference associates the R80101T union family with the Permaswage® D10036/D10136 union families.
This provides a useful starting point for identifying a related Permaswage® fitting, but it does not establish an individually approved replacement part number or confirm that the NSN applies to a Permaswage® product.
Does a Cross-Reference Mean the Fittings Are Interchangeable?
Not necessarily. A historical cross-reference is useful for identifying related product families, but it does not automatically authorize substitution in an aircraft fluid system.
Before replacing one fitting with another, maintenance and engineering personnel should verify:
- Exact fitting configuration and port arrangement
- Tube outside diameter and size designation
- Fitting material
- Pressure and temperature requirements
- Applicable aerospace specifications
- Installation requirements
- Approved maintenance or engineering documentation
- Operator and quality-system requirements
Rynglok® and Permaswage® are distinct fitting systems. A family-level cross-reference should never be interpreted as permission to mix installation methods, tooling, or components without appropriate technical authorization.
Historical Aeroquip Reference Documentation
The information in this guide was compiled from historical Aeroquip reference sheets identifying Rynglok®-to-Permaswage® fitting family relationships and Rynglok® fitting National Stock Numbers.
The source materials include four pages of fitting-family cross-references and seven pages of NSN listings. The NSN source carries a revision date of April 15, 1997.
The NSN entries published in this article represent selected records transcribed into the reference workbook. They are not a complete reproduction of the original seven-page NSN listing and should not be interpreted as a current government supply-catalog verification.
Frequently Asked Questions
Can I cross-reference an Aeroquip Rynglok® part number to a Permaswage® part number?
Historical Aeroquip documentation identifies numerous corresponding Rynglok® and Permaswage® fitting families. These references can help identify a potential related part family, but exact part-number relationships and interchangeability must be verified.
Can I search for Rynglok® fittings by NSN?
Yes. Historical Rynglok® documentation includes National Stock Numbers for numerous fitting part numbers. The NSN can be used as a starting point for researching military inventory and legacy aerospace supply records.
Does a Rynglok® NSN also identify the corresponding Permaswage® fitting?
Not automatically. The NSNs in this guide are recorded against Rynglok® part numbers. A family cross-reference does not establish that the same NSN applies to a Permaswage® fitting.
Are Rynglok® and Permaswage® fittings interchangeable?
A historical part-number cross-reference does not independently establish interchangeability. Any proposed substitution must be evaluated against the applicable aircraft maintenance data, engineering requirements, material specifications, and approval procedures.
Why are historical part-number cross-references useful?
They can assist procurement teams, repair stations, and maintenance personnel in identifying legacy fittings, interpreting older inventory records, and researching potentially related product families.
Top Flight Tools — Aerospace Fitting Identification and Sourcing
Top Flight Tools specializes in genuine OEM aerospace tooling and supports customers researching Permaswage®, Rynglok®, and related aircraft tube-connection equipment.
Our goal is to help aerospace customers identify the correct products, understand manufacturer part-number distinctions, and make informed purchasing decisions based on their technical and documentation requirements.
When researching legacy fittings or National Stock Numbers, providing the complete part number, NSN, fitting description, and any available manufacturer documentation can help streamline the identification process.
Conclusion
Historical Aeroquip Rynglok®-to-Permaswage® cross-reference documentation provides a valuable starting point for identifying related aerospace fitting families.
Combined with Rynglok® National Stock Number listings, these references can assist with legacy aircraft support, military procurement research, and fitting identification.
However, a part-number cross-reference or shared fitting configuration should never be treated as automatic evidence of interchangeability, current qualification, or installation approval.
Always verify the exact fitting part number, material, size, application, and applicable maintenance or engineering requirements before selecting a replacement.
⚠️ Disclaimer
Top Flight Tools (TFT) is an independent reseller and is not affiliated with, sponsored by, or endorsed by Permaswage®, Precision Castparts Corp. (PCC), Aeroquip, or Eaton. All product names, trademarks, and registered trademarks are the property of their respective owners. Any reference to Permaswage®, Rynglok®, manufacturer part numbers, or National Stock Numbers is provided for informational and identification purposes only.
The cross-reference and NSN information presented in this article is derived from historical reference documentation and has not been independently verified as current manufacturer or government supply data. Cross-referenced part numbers do not automatically establish interchangeability, qualification, or approval for aircraft installation.
While every effort is made to ensure the accuracy of the information provided, it is the customer's responsibility to verify all specifications, compatibility, traceability, and suitability of products for their intended application prior to use. TFT assumes no liability for errors, omissions, or the misuse or misapplication of this information, and disclaims any responsibility for damages resulting from reliance on it.