The Screw,shoulder, cataloged under National Stock Number 5305-01-617-9878, 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 6 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5305-01-617-9878 |
| Primary Part Number | AES20U312500BB3A81 |
| Item Name | Screw,shoulder |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The American Society of Mechanical Engineers |
| Status | ACTIVE |
| Thread Length | 0.500 INCHES NOMINAL IN |
| Nominal Thread Diameter | 0.3125 INCHES IN |
| Surface Treatment | ZINC OVERALL |
| Internal Drive Style | HEXAGON |
| 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 |
|---|---|
| AES20U312500BB3A81 PRIMARY | The American Society of Mechanical Engineers (USA) |
| AES20U312500BB3A81 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| B183A031C050HSHS | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-617-9878 is a Screw,shoulder, manufactured by The American Society of Mechanical Engineers, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-617-9878 has 2 manufacturer part numbers on file: AES20U312500BB3A81 (The American Society of Mechanical Engineers), AES20U312500BB3A81 (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for AES20U312500BB3A81: Thread Length: 0.500 INCHES NOMINAL IN; Nominal Thread Diameter: 0.3125 INCHES IN; Special Features: MATERAIL: ASTM A574 ALLOY STEEL; Surface Treatment: ZINC OVERALL. 6 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.