The Nut,self-Locking,slotted,hexagon, cataloged under National Stock Number 5310-01-346-0137, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Sps Technologies, Llc Dba PB Fasteners. Government technical data includes 13 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-346-0137 |
| Primary Part Number | 59-FK-640 |
| Item Name | Nut,self-Locking,slotted,hexagon |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Sps Technologies, Llc Dba PB Fasteners |
| Status | ACTIVE |
| Width Across Flats | 0.305 INCHES MINIMUM AND 0.313 INCHES MAXIMUM IN |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Precious Material | SILVER |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.138 INCHES IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Nut Height | 0.141 INCHES MAXIMUM IN |
| Surface Treatment | SILVER OVERALL |
| Nut Style | SLOTTED, HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 40 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Bearing Surface Type | CHAMFERED |
| 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 |
|---|---|
| 59-FK-640 PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| 59-FX-640 | 5/9 Secondary reference U.S. Government activity |
| 59-FK-640 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
NSN 5310-01-346-0137 is a Nut,self-Locking,slotted,hexagon, manufactured by Sps Technologies, Llc Dba PB Fasteners, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-346-0137 has 1 manufacturer part number on file: 59-FK-640 (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for 59-FK-640: Width Across Flats: 0.305 INCHES MINIMUM AND 0.313 INCHES MAXIMUM IN; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Precious Material: SILVER; Thread Direction: RIGHT-HAND. 13 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.