The Ring,retaining, cataloged under National Stock Number 5325-00-804-6857, is classified within Federal Supply Class 5325 (Fastening Devices) of the Hardware and Abrasives group. The manufacturer of record is Leonardo Spa Helicopters Division - Production Site. 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through both NSN and commercial part number lookups. 8 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5325-00-804-6857 |
| Primary Part Number | MS16625-4051 |
| Item Name | Ring,retaining |
| FSC / FSG | 5325 / 53 — Fastening Devices |
| Manufacturer | Leonardo Spa Helicopters Division - Production Site |
| Status | ACTIVE |
| Material Hardness Rating | 63.0 ROCKWELL SUPERFICIAL 30-N MINIMUM AND 69.5 ROCKWELL SUPERFICIAL 30-N MAXIMUM |
| Usage Design | INTERNAL |
| Material Document and Classification | AMS 5520 ASSN STD SINGLE MATERIAL RESPONSE |
| Cross-Sectional Shape Style | RECTANGULAR |
| Outside Diameter | 0.555 INCHES MINIMUM AND 0.570 INCHES MAXIMUM IN |
| Major Thickness | 0.033 INCHES MINIMUM AND 0.037 INCHES MAXIMUM IN |
| Casehardening Indicator | NOT CASEHARDENED |
| Ring Style | INTERNAL |
| Surface Treatment | PASSIVATE |
| Material | STEEL COMP 632 |
| 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 |
|---|---|
| MS16625-4051 | Leonardo Spa Helicopters Division - Production Site (ITA) |
| Reference | Meaning |
|---|---|
| N5000-51H | C/1 Advisory reference — outside the item-of-supply concept Rotor Clip Company, Inc. |
| N5000-51H | 5/9 Secondary reference Truarc Company Llc Dba Waldes Truarc |
| N5000-X51-H | C/1 Advisory reference — outside the item-of-supply concept Rotor Clip Company, Inc. |
| N1300-51AS | 5/9 Secondary reference Seeger Inc Anderton-United Products Div |
| MIL-DTL-21248 | 4/1 Identification reference U.S. Government activity |
| MS16625-4051 | 2/2 Government specification standardization U.S. Government activity |
| N5000-X51-H | 5/9 Secondary reference Truarc Company Llc Dba Waldes Truarc |
| 5000-51W | C/1 Advisory reference — outside the item-of-supply concept Truarc Company Llc Dba Waldes Truarc |
NSN 5325-00-804-6857 is a Ring,retaining, manufactured by Leonardo Spa Helicopters Division - Production Site, classified under FSC 5325, Fastening Devices. Status: active.
NSN 5325-00-804-6857 has 1 manufacturer part number on file: MS16625-4051 (Leonardo Spa Helicopters Division - Production Site).
Key specifications for MS16625-4051: Material Hardness Rating: 63.0 ROCKWELL SUPERFICIAL 30-N MINIMUM AND 69.5 ROCKWELL SUPERFICIAL 30-N MAXIMUM; Usage Design: INTERNAL; Material Document and Classification: AMS 5520 ASSN 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.