The Nut,self-Locking,extended Washer, cataloged under National Stock Number 5310-01-194-0673, 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 17 specifications, cited from the U.S. Government catalog. The record lists 4 manufacturer part numbers 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-194-0673 |
| Primary Part Number | ST3M737-6 |
| Item Name | Nut,self-Locking,extended Washer |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Lubrication | DRY FILM LUBRICANT |
| Washer Outside Diameter | 0.677 INCHES MAXIMUM IN |
| Width Across Flats | 0.424 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | AMS 2401 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Temp Rating | 450.0 FAHRENHEIT MAXIMUM DEGF |
| Hardness Rating | 45.0 ROCKWELL C MAXIMUM |
| Washer Thickness | 0.060 INCHES NOMINAL IN |
| Material Document and Classification | AMS 6304 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.375 INCHES IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Surface Treatment | CADMIUM OVERALL |
| Nut Style | DOUBLE HEXAGON |
| Thread Class | 2B |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 601 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 |
|---|---|
| ST3M737-6 PRIMARY | The Boeing Company Div Defense (USA) |
| ST3M737-6 | Howmet Global Fastening Systems Inc (USA) |
| H50675-6 | T E Rocks Fasteners (USA) |
| 78351-624 PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| H50675-6 | 5/9 Secondary reference Howmet Global Fastening Systems Inc |
| LH12343-6 | 5/9 Secondary reference Harvard Industries Inc |
NSN 5310-01-194-0673 is a Nut,self-Locking,extended Washer, manufactured by The Boeing Company Div Defense, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-194-0673 has 4 manufacturer part numbers on file: ST3M737-6 (The Boeing Company Div Defense), ST3M737-6 (Howmet Global Fastening Systems Inc), H50675-6 (T E Rocks Fasteners), 78351-624 (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for ST3M737-6: Lubrication: DRY FILM LUBRICANT; Overall Height: 0.458 INCHES MAXIMUM IN; Washer Outside Diameter: 0.677 INCHES MAXIMUM IN; Width Across Flats: 0.424 INCHES MINIMUM AND 0.439 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.