The Ring,retaining, cataloged under National Stock Number 5325-00-285-1318, is classified within Federal Supply Class 5325 (Fastening Devices) of the Hardware and Abrasives group. The manufacturer of record is Cirteq Ltd. Government technical data includes 10 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5325-00-285-1318 |
| Primary Part Number | 5131-18 |
| Item Name | Ring,retaining |
| FSC / FSG | 5325 / 53 — Fastening Devices |
| Manufacturer | Cirteq Ltd |
| Status | ACTIVE |
| Material Hardness Rating | 84.5 ROCKWELL SUPERFICIAL 15-N MINIMUM AND 87.0 ROCKWELL SUPERFICIAL 15-N MAXIMUM |
| Usage Design | EXTERNAL |
| Material Document and Classification | FED STD NO. 66 FS1066 TO FS1090 FED STD SINGLE MATERIAL RESPONSE |
| Cross-Sectional Shape Style | RECTANGULAR |
| End Play Takeup | 0.015 INCHES MAXIMUM IN |
| Major Thickness | 0.015 INCHES NOMINAL IN |
| Inside Diameter | 0.145 INCHES NOMINAL IN |
| Casehardening Indicator | NOT CASEHARDENED |
| Ring Style | E BOWED |
| Material | STEEL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 5131-18 | Cirteq Ltd (GBR) |
| Reference | Meaning |
|---|---|
| 5131-18 | 5/9 Secondary reference Truarc Company Llc Dba Waldes Truarc |
| N1501-18AS | 5/9 Secondary reference Seeger Inc Anderton-United Products Div |
| MS16634-18 | 2/2 Government specification standardization U.S. Government activity |
| N1501-18 | 5/9 Secondary reference Seeger Inc Anderton-United Products Div |
| N1501-18CD | 5/9 Secondary reference Seeger Inc Anderton-United Products Div |
| 4000765 | 5/9 Secondary reference H & E Venture, Llc |
| 5131-18 | C/1 Advisory reference — outside the item-of-supply concept Rotor Clip Company, Inc. |
NSN 5325-00-285-1318 is a Ring,retaining, manufactured by Cirteq Ltd, classified under FSC 5325, Fastening Devices. Status: active.
NSN 5325-00-285-1318 has 1 manufacturer part number on file: 5131-18 (Cirteq Ltd).
1 possible match (shared part number, not a government interchangeability claim): 6515-01-215-2621. Verify interchangeability with system specifications before substitution.
Key specifications for 5131-18: Material Hardness Rating: 84.5 ROCKWELL SUPERFICIAL 15-N MINIMUM AND 87.0 ROCKWELL SUPERFICIAL 15-N MAXIMUM; Usage Design: EXTERNAL; Material Document and Classification: FED STD NO. 66 FS1066 TO FS1090 FED STD SINGLE MATERIAL RESPONSE; Cross-Sectional Shape Style: RECTANGULAR. 10 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.