The Screw,machine, cataloged under National Stock Number 5305-01-043-5686, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Keuffel and Esser Co. Government technical data includes 12 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-043-5686 |
| Primary Part Number | P256-2SS |
| Item Name | Screw,machine |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Keuffel and Esser Co |
| Status | ACTIVE |
| Head Height | 0.045 INCHES MINIMUM AND 0.053 INCHES MAXIMUM IN |
| Fastener Length | 0.125 INCHES NOMINAL IN |
| Thread Length | 0.063 INCHES MINIMUM IN |
| Nominal Thread Diameter | 0.086 INCHES IN |
| Head Style | PAN NO. 2 |
| Thread Direction | RIGHT-HAND |
| Screw Material | STEEL CORROSION RESISTING |
| Internal Drive Style | SLOT |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 56 |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.155 INCHES MINIMUM AND 0.167 INCHES MAXIMUM IN |
| 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 |
|---|---|
| P256-2SS PRIMARY | Keuffel and Esser Co (USA) |
| Reference | Meaning |
|---|---|
| P256-2SS | 3/9 Design control — primary reference Brunson Instrument Company Dba Brunson Instrument Company |
NSN 5305-01-043-5686 is a Screw,machine, manufactured by Keuffel and Esser Co, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-043-5686 has 1 manufacturer part number on file: P256-2SS (Keuffel and Esser Co).
Key specifications for P256-2SS: Head Height: 0.045 INCHES MINIMUM AND 0.053 INCHES MAXIMUM IN; Fastener Length: 0.125 INCHES NOMINAL IN; Thread Length: 0.063 INCHES MINIMUM IN; Nominal Thread Diameter: 0.086 INCHES IN. 12 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.