The Nut,self-Locking,plate, cataloged under National Stock Number 5310-01-030-1811, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company Div Defense. Government technical data includes 21 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-030-1811 |
| Primary Part Number | ST3M721C4M6 |
| Item Name | Nut,self-Locking,plate |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Lubrication | DRY FILM LUBRICANT |
| Nut Length | 1.079 INCHES MAXIMUM IN |
| Thread Series | UNF |
| Mounting Hole Arrangement Style | 2 HOLES |
| Material Document and Classification | AMS5525 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Mounting Hole Diameter | 0.098 INCHES MINIMUM AND 0.103 INCHES MAXIMUM IN |
| Nut Counterbore Depth | 0.375 INCHES MINIMUM NUT IN |
| Features Provided | FLOATING NUT |
| Thread Direction | RIGHT-HAND |
| Center to Center Distance Between Mounting Holes Along Width | 0.705 INCHES MINIMUM AND 0.709 INCHES MAXIMUM IN |
| Nominal Thread Size | 0.250 INCHES IN |
| Specification/standard Data | 76301-ST3-721 MANUFACTURERS STANDARD |
| Counterbore Diameter | 0.298 INCHES MINIMUM NUT IN |
| Distance From Aperture Center to Mounting Hole Center | 0.495 INCHES MINIMUM AND 0.505 INCHES MAXIMUM IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Nut Height | 0.589 INCHES MAXIMUM IN |
| Nut Style | PLATE |
| Thread Class | 2B |
| Thread Quantity Per Inch | 28 |
| Material | IRON ALLOY 660 OVERALL |
| Nut Mounting Provision | STRAIGHT HOLES |
| 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 |
|---|---|
| ST3M721C4M6 PRIMARY | The Boeing Company Div Defense (USA) |
| F50403-4-6 PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| 10122007 | 6/9 Informative reference only Nimikkeistokeskus Ncb Finland |
| F12092-6-4 | 5/9 Secondary reference Harvard Industries Inc |
| NS202183-4-7 | 3/2 Design control — primary reference U.S. Government activity |
| F50403-4-6 | 5/9 Secondary reference U.S. Government activity |
| F12092-6-4 | 5/2 Secondary reference U.S. Government activity |
NSN 5310-01-030-1811 is a Nut,self-Locking,plate, manufactured by The Boeing Company Div Defense, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-030-1811 has 2 manufacturer part numbers on file: ST3M721C4M6 (The Boeing Company Div Defense), F50403-4-6 (Howmet Global Fastening Systems Inc).
Key specifications for ST3M721C4M6: Lubrication: DRY FILM LUBRICANT; Nut Length: 1.079 INCHES MAXIMUM IN; Thread Series: UNF; Mounting Hole Arrangement Style: 2 HOLES. 21 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.