The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-678-7221, 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 11 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-678-7221 |
| Primary Part Number | AES14U312D50BB3MF1 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The American Society of Mechanical Engineers |
| Status | ACTIVE |
| Fastener Length | 4.5 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | ASTM B633 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Material Document and Classification | ASTM A574 AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.3125 INCHES IN |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | ZINC OVERALL |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 18 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| 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 |
|---|---|
| AES14U312D50BB3MF1 PRIMARY | The American Society of Mechanical Engineers (USA) |
NSN 5305-01-678-7221 is a Screw,cap,socket Head, manufactured by The American Society of Mechanical Engineers, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-678-7221 has 1 manufacturer part number on file: AES14U312D50BB3MF1 (The American Society of Mechanical Engineers).
Key specifications for AES14U312D50BB3MF1: Fastener Length: 4.5 INCHES NOMINAL IN; Surface Treatment Document and Classification: ASTM B633 ASSN STD SINGLE TREATMENT RESPONSE OVERALL; Material Document and Classification: ASTM A574 AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) SINGLE MATERIAL RESPONSE OVERALL; Nominal Thread Diameter: 0.3125 INCHES IN. 11 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.