The Nut,self-Locking,extended Washer, cataloged under National Stock Number 5310-01-181-9340, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company. Government technical data includes 17 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-181-9340 |
| Primary Part Number | HS4270-624 |
| Item Name | Nut,self-Locking,extended Washer |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | The Boeing Company |
| Status | ACTIVE |
| Washer Outside Diameter | 0.688 INCHES MAXIMUM IN |
| Width Across Flats | 0.492 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Temp Rating | 450.0 FAHRENHEIT MAXIMUM DEGF |
| Hardness Rating | 38.0 ROCKWELL C MAXIMUM |
| Washer Thickness | 0.103 INCHES MINIMUM IN |
| Material Document and Classification | AMS 6280 ASSN STD 1ST MATERIAL RESPONSE OR AMS 6300 ASSN STD 2ND MATERIAL RESPONSE OR AMS 6322 ASSN STD 3RD MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.375 INCHES IN |
| Counterbore Diameter | 0.421 INCHES MAXIMUM FIRST END IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Surface Treatment | CADMIUM OVERALL |
| Nut Style | DOUBLE HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 8630 OR STEEL COMP 4037 OR STEEL COMP 8740 OVERALL |
| 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 |
|---|---|
| HS4270-624 PRIMARY | The Boeing Company (USA) |
| Reference | Meaning |
|---|---|
| HS4270-624 | 3/9 Design control — primary reference Mcdonnell Douglas Helicopter Co Inc |
| 42FW-624 | 5/2 Secondary reference U.S. Government activity |
NSN 5310-01-181-9340 is a Nut,self-Locking,extended Washer, manufactured by The Boeing Company, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-181-9340 has 1 manufacturer part number on file: HS4270-624 (The Boeing Company).
1 possible match (shared part number, not a government interchangeability claim): 5310-01-378-8179. Verify interchangeability with system specifications before substitution.
Key specifications for HS4270-624: Overall Height: 0.458 INCHES MAXIMUM IN; Washer Outside Diameter: 0.688 INCHES MAXIMUM IN; Width Across Flats: 0.492 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL. 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.