The Screw,shoulder, cataloged under National Stock Number 5305-01-321-3573, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. Government technical data includes 20 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-321-3573 |
| Item Name | Screw,shoulder |
| FSC / FSG | 5305 / 53 — Screws |
| Status | ACTIVE |
| Width Across Flats | 0.125 INCHES NOMINAL IN |
| Head Height | 0.156 INCHES MINIMUM AND 0.219 INCHES MAXIMUM IN |
| Fastener Length | 0.524 INCHES MINIMUM AND 0.597 INCHES MAXIMUM IN |
| Shoulder Length | 0.313 INCHES MINIMUM AND 0.316 INCHES MAXIMUM FIRST SHOULDER IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Shoulder Diameter | 0.2485 INCHES MINIMUM AND 0.2495 INCHES MAXIMUM FIRST SHOULDER IN |
| Thread Length | 0.211 INCHES MINIMUM AND 0.281 INCHES MAXIMUM IN |
| Shoulder Shape | ROUND FIRST SHOULDER |
| Hardness Rating | 32.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | ASTM A582 ASSN STD 1ST MATERIAL RESPONSE OR ASTM A493 ASSN STD 2ND MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.190 INCHES IN |
| Head Style | FLAT CHAMFER |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | STEEL COMP 303 OR STEEL COMP 304 OVERALL |
| Thread Series Designator | UNF |
| Head Diameter | 0.344 INCHES MINIMUM AND 0.406 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 |
| Reference | Meaning |
|---|---|
| MS51576-18 | 2/2 Government specification standardization U.S. Government activity |
NSN 5305-01-321-3573 is a Screw,shoulder, classified under FSC 5305, Screws. Status: active.
Key specifications for 5305-01-321-3573: Width Across Flats: 0.125 INCHES NOMINAL IN; Head Height: 0.156 INCHES MINIMUM AND 0.219 INCHES MAXIMUM IN; Fastener Length: 0.524 INCHES MINIMUM AND 0.597 INCHES MAXIMUM IN; Shoulder Length: 0.313 INCHES MINIMUM AND 0.316 INCHES MAXIMUM FIRST SHOULDER IN. 20 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.