The Ring,retaining, cataloged under National Stock Number 5325-00-307-1638, is classified within Federal Supply Class 5325 (Fastening Devices) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company Div Defense. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5325-00-307-1638 |
| Primary Part Number | 9M188-87 |
| Item Name | Ring,retaining |
| FSC / FSG | 5325 / 53 — Fastening Devices |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Usage Design | INTERNAL |
| Material Document and Classification | SAE OR AISI 1070-1090 ASSN STD SINGLE MATERIAL RESPONSE |
| Cross-Sectional Shape Style | DOUBLE OVAL |
| Outside Diameter | 0.929 INCHES MINIMUM AND 0.942 INCHES MAXIMUM IN |
| Major Thickness | 0.042 INCHES MINIMUM AND 0.046 INCHES MAXIMUM IN |
| Inside Diameter | 0.799 INCHES MINIMUM AND 0.812 INCHES MAXIMUM IN |
| Casehardening Indicator | NOT CASEHARDENED |
| Ring Style | SPIRAL |
| Surface Treatment | CADMIUM AND CHROMATE |
| 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 |
|---|---|
| 9M188-87 | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| RRT87CDM9 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5325-00-307-1638 is a Ring,retaining, manufactured by The Boeing Company Div Defense, classified under FSC 5325, Fastening Devices. Status: active.
NSN 5325-00-307-1638 has 1 manufacturer part number on file: 9M188-87 (The Boeing Company Div Defense).
Key specifications for 9M188-87: Usage Design: INTERNAL; Material Document and Classification: SAE OR AISI 1070-1090 ASSN STD SINGLE MATERIAL RESPONSE; Cross-Sectional Shape Style: DOUBLE OVAL; Outside Diameter: 0.929 INCHES MINIMUM AND 0.942 INCHES MAXIMUM IN. 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.