The Nut,plain,hexagon, cataloged under National Stock Number 5310-01-320-8087, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Defense Logistics Agency Dba Defense Supply Center Philadelphia. Government technical data includes 16 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5310-01-320-8087 |
| Primary Part Number | 03A251-4C |
| Item Name | Nut,plain,hexagon |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Defense Logistics Agency Dba Defense Supply Center Philadelphia |
| Status | ACTIVE |
| Width Across Flats | 0.428 INCHES MINIMUM AND 0.440 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Hole Configuration Style | CONFIGURATION B |
| Material Document and Classification | AMS 5525 ASSN STD SINGLE MATERIAL RESPONSE OR AMS 5732 ASSN STD SINGLE MATERIAL RESPONSE OR AMS 5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.250 INCHES IN |
| Nut Height | 0.178 INCHES MINIMUM AND 0.198 INCHES MAXIMUM IN |
| Drilled Hole Diameter | 0.045 INCHES MINIMUM AND 0.050 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Nut Style | HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 28 |
| Material | IRON ALLOY 660 OVERALL |
| Bearing Surface Type | CHAMFERED |
| Hole Type and Quantity | 3 DRILLED |
| 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 |
|---|---|
| T-1156-4C | Long-Lok, Llc (USA) |
| 03A251-4C | Northrop Grumman Systems Corp Dba Northrop Grumman Computing Systems (USA) |
| H52862-4C | Howmet Global Fastening Systems Inc (USA) |
| 03A251-4C | Long-Lok Llc (USA) |
| T-1156-4C | Long-Lok Llc (USA) |
| 03A251-4C PRIMARY | Defense Logistics Agency Dba Defense Supply Center Philadelphia (USA) |
| Reference | Meaning |
|---|---|
| AD03A251-4C | 5/2 Secondary reference U.S. Government activity |
NSN 5310-01-320-8087 is a Nut,plain,hexagon, manufactured by Defense Logistics Agency Dba Defense Supply Center Philadelphia, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-320-8087 has 6 manufacturer part numbers on file: T-1156-4C (Long-Lok, Llc), 03A251-4C (Northrop Grumman Systems Corp Dba Northrop Grumman Computing Systems), H52862-4C (Howmet Global Fastening Systems Inc), 03A251-4C (Long-Lok Llc), T-1156-4C (Long-Lok Llc) and 1 more.
Key specifications for 03A251-4C: Width Across Flats: 0.428 INCHES MINIMUM AND 0.440 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Hole Configuration Style: CONFIGURATION B. 16 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.