The Nut,self-Locking,extended Washer, cataloged under National Stock Number 5310-00-677-0659, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Huck International, Inc. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 6 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5310-00-677-0659 |
| Primary Part Number | NAS1291-8 |
| Item Name | Nut,self-Locking,extended Washer |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Huck International, Inc |
| Status | ACTIVE |
| Lubrication | DRY FILM LUBRICANT |
| Washer Outside Diameter | 0.814 INCHES MAXIMUM IN |
| Width Across Flats | 0.556 INCHES MINIMUM AND 0.566 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Temp Rating | 450.0 FAHRENHEIT NOMINAL DEGF |
| Criticality Code Justification | FEAT |
| Washer Thickness | 0.040 INCHES MINIMUM IN |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.500 INCHES IN |
| Specification/standard Data | 80205-NAS1291 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Surface Treatment | CADMIUM OVERALL |
| Nut Style | HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 20 |
| Material | STEEL OVERALL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | F |
| Part Number | Manufacturer |
|---|---|
| NAS1291-8 | Huck International, Inc (USA) |
| NAS1291-8 | Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp (USA) |
| NAS1291-8 | Bristol Industries, Llc (USA) |
| NAS1291-8 | Esna, Llc (USA) |
| NAS1291-8 | Paolo Astori Spa (ITA) |
| NAS1291-8 | Adept Fasteners Inc (USA) |
| Reference | Meaning |
|---|---|
| NAS1291-8 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5310-00-677-0659 is a Nut,self-Locking,extended Washer, manufactured by Huck International, Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-677-0659 has 6 manufacturer part numbers on file: NAS1291-8 (Huck International, Inc), NAS1291-8 (Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp), NAS1291-8 (Bristol Industries, Llc), NAS1291-8 (Esna, Llc), NAS1291-8 (Paolo Astori Spa) and 1 more.
Key specifications for NAS1291-8: Lubrication: DRY FILM LUBRICANT; Overall Height: 0.350 INCHES MINIMUM AND 0.410 INCHES MAXIMUM IN; Washer Outside Diameter: 0.814 INCHES MAXIMUM IN; Width Across Flats: 0.556 INCHES MINIMUM AND 0.566 INCHES MAXIMUM IN. 17 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.