The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-256-5197, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is The American Society of Mechanical Engineers. Government technical data includes 14 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-256-5197 |
| Primary Part Number | AES18U138500EA3A31 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The American Society of Mechanical Engineers |
| Status | ACTIVE |
| Width Across Flats | 0.078 INCHES NOMINAL IN |
| Head Height | 0.063 INCHES MINIMUM AND 0.073 INCHES MAXIMUM IN |
| Fastener Length | 0.470 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN |
| Thread Length | 0.408 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.138 INCHES IN |
| Head Style | BUTTON |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.250 INCHES MINIMUM AND 0.262 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 |
|---|---|
| AES18U138500EA3A31 | The American Society of Mechanical Engineers (USA) |
| Reference | Meaning |
|---|---|
| 38031-96C-8 | 5/9 Secondary reference Sps Technologies, Llc Dba PB Fasteners |
| 38031-96C-8 | 3/2 Design control — primary reference U.S. Government activity |
| 94703-96C-8 | 5/9 Secondary reference Sps Technologies, Llc Dba PB Fasteners |
NSN 5305-01-256-5197 is a Screw,cap,socket Head, manufactured by The American Society of Mechanical Engineers, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-256-5197 has 1 manufacturer part number on file: AES18U138500EA3A31 (The American Society of Mechanical Engineers).
Key specifications for AES18U138500EA3A31: Width Across Flats: 0.078 INCHES NOMINAL IN; Head Height: 0.063 INCHES MINIMUM AND 0.073 INCHES MAXIMUM IN; Fastener Length: 0.470 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN; Thread Length: 0.408 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN. 14 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.