The Washer,key, cataloged under National Stock Number 5310-00-286-9650, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Hf Group Inc Dba Hf Group Inc. Government technical data includes 15 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. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-286-9650 |
| Primary Part Number | 1028721 |
| Item Name | Washer,key |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Hf Group Inc Dba Hf Group Inc |
| Status | ACTIVE |
| Internal Straight Key Width | 0.075 INCHES MINIMUM AND 0.085 INCHES MAXIMUM IN |
| Distance From Centerline to Top of Internal Key | 0.161 INCHES NOMINAL IN |
| Distance From Centerline to Inside of Prebent Key | 0.679 INCHES NOMINAL IN |
| External Prebent Key Length | 0.084 INCHES NOMINAL IN |
| Overall Distance Including Keys | 1.235 INCHES MINIMUM AND 1.265 INCHES MAXIMUM IN |
| Style Designator | KEY |
| Material Document and Classification | MIL-S-5059 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 1.088 INCHES MINIMUM AND 1.098 INCHES MAXIMUM IN |
| Material Thickness | 0.025 INCHES NOMINAL IN |
| External Key Quantity | 1 |
| Surface Treatment | PASSIVATE OVERALL |
| External Prebent Key Width | 0.075 INCHES MINIMUM AND 0.085 INCHES MAXIMUM IN |
| Material | STEEL COMP 302 OVERALL |
| Internal Key Quantity | 1 |
| Hole Diameter | 0.510 INCHES MINIMUM AND 0.511 INCHES MAXIMUM IN |
| 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 |
|---|---|
| 1028721 PRIMARY | Hf Group Inc Dba Hf Group Inc (USA) |
NSN 5310-00-286-9650 is a Washer,key, manufactured by Hf Group Inc Dba Hf Group Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-286-9650 has 1 manufacturer part number on file: 1028721 (Hf Group Inc Dba Hf Group Inc).
2 possible matches (shared part number, not a government interchangeability claim): 1680-01-600-5993, 5930-01-612-7125. Verify interchangeability with system specifications before substitution.
Key specifications for 1028721: Internal Straight Key Width: 0.075 INCHES MINIMUM AND 0.085 INCHES MAXIMUM IN; Distance From Centerline to Top of Internal Key: 0.161 INCHES NOMINAL IN; Distance From Centerline to Inside of Prebent Key: 0.679 INCHES NOMINAL IN; External Prebent Key Length: 0.084 INCHES NOMINAL IN. 15 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.