The Ring,retaining, cataloged under National Stock Number 5325-01-478-0541, is classified within Federal Supply Class 5325 (Fastening Devices) of the Hardware and Abrasives group. The manufacturer of record is Howmet Global Fastening Systems Inc. Div Tridair Products. Government technical data includes 8 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5325-01-478-0541 |
| Primary Part Number | CA21135-M4R |
| Item Name | Ring,retaining |
| FSC / FSG | 5325 / 53 — Fastening Devices |
| Manufacturer | Howmet Global Fastening Systems Inc. Div Tridair Products |
| Status | ACTIVE |
| Material Document and Classification | MIL-S-25043 MIL SPEC SINGLE MATERIAL RESPONSE |
| Cross-Sectional Shape Style | ROUNDED CORNERS |
| Outside Diameter | 6.045 MILLIMETERS MINIMUM AND 6.198 MILLIMETERS MAXIMUM MM |
| Major Thickness | 0.330 MILLIMETERS MINIMUM AND 0.432 MILLIMETERS MAXIMUM MM |
| Inside Diameter | 4.521 MILLIMETERS MINIMUM AND 4.674 MILLIMETERS MAXIMUM MM |
| Ring Style | SPLIT |
| Surface Treatment | PASSIVATE |
| Material | STEEL COMP 631 |
| 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 |
|---|---|
| CA21135-M4R PRIMARY | Howmet Global Fastening Systems Inc. Div Tridair Products (USA) |
NSN 5325-01-478-0541 is a Ring,retaining, manufactured by Howmet Global Fastening Systems Inc. Div Tridair Products, classified under FSC 5325, Fastening Devices. Status: active.
NSN 5325-01-478-0541 has 1 manufacturer part number on file: CA21135-M4R (Howmet Global Fastening Systems Inc. Div Tridair Products).
Key specifications for CA21135-M4R: Material Document and Classification: MIL-S-25043 MIL SPEC SINGLE MATERIAL RESPONSE; Cross-Sectional Shape Style: ROUNDED CORNERS; Outside Diameter: 6.045 MILLIMETERS MINIMUM AND 6.198 MILLIMETERS MAXIMUM MM; Major Thickness: 0.330 MILLIMETERS MINIMUM AND 0.432 MILLIMETERS MAXIMUM MM. 8 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.