The Nut,self-Locking,hexagon, cataloged under National Stock Number 5310-01-025-6991, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Howmet Global Fastening Systems Inc. Government technical data includes 18 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-025-6991 |
| Primary Part Number | H31-10BAC |
| Item Name | Nut,self-Locking,hexagon |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Howmet Global Fastening Systems Inc |
| Status | ACTIVE |
| Width Across Flats | 0.928 INCHES MINIMUM AND 0.940 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | AMS 2410 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Precious Material | SILVER |
| Temp Rating | 900.0 FAHRENHEIT NOMINAL DEGF |
| Material Document and Classification | AMS5525 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.625 INCHES IN |
| Specification/standard Data | 81205-BACN10JC MANUFACTURERS STANDARD |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Nut Height | 0.407 INCHES MAXIMUM IN |
| Surface Treatment | SILVER OVERALL |
| Countersink Angle | 120.0 DEGREES NOMINAL NUT |
| Nut Style | HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 18 |
| Material | IRON ALLOY 660 OVERALL |
| Bearing Surface Type | CHAMFERED OR WASHER FACED |
| 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 |
|---|---|
| H31-10BAC PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| BMN4122C15-10 | 5/9 Secondary reference U.S. Government activity |
| BACN10JC10C | 5/2 Secondary reference U.S. Government activity |
| 101LH9074-10 | 5/9 Secondary reference Harvard Industries Inc |
| BMN4122C15-10 | C/1 Advisory reference — outside the item-of-supply concept Huck International, Inc |
NSN 5310-01-025-6991 is a Nut,self-Locking,hexagon, manufactured by Howmet Global Fastening Systems Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-025-6991 has 1 manufacturer part number on file: H31-10BAC (Howmet Global Fastening Systems Inc).
Key specifications for H31-10BAC: Width Across Flats: 0.928 INCHES MINIMUM AND 0.940 INCHES MAXIMUM IN; Surface Treatment Document and Classification: AMS 2410 ASSN STD SINGLE TREATMENT RESPONSE OVERALL; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Precious Material: SILVER. 18 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.