The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-379-9947, 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20 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-379-9947 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Status | ACTIVE |
| Width Across Flats | 0.187 INCHES MINIMUM AND 0.190 INCHES MAXIMUM IN |
| Head Height | 0.244 INCHES MINIMUM AND 0.250 INCHES MAXIMUM IN |
| Fastener Length | 0.500 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | MIL-C-13924 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.400 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN |
| Hardness Rating | 33.0 ROCKWELL C MINIMUM AND 42.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | AMS5731 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT CHAMFER |
| Thread Direction | RIGHT-HAND |
| Color | BLACK OVERALL |
| Surface Treatment | OXIDE OVERALL |
| Minimum Tensile Strength | 160000 POUNDS PER SQUARE INCH LBS |
| Minimum Yield Strength | 120000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 20 |
| Material | IRON ALLOY 660 OVERALL |
| Thread Series Designator | UNRC |
| Head Diameter | 0.365 INCHES MINIMUM AND 0.375 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 |
|---|---|
| NAS1352N4-8B | 3/2 Design control — primary reference U.S. Government activity |
| FF-S-86 | 4/1 Identification reference U.S. Government activity |
NSN 5305-01-379-9947 is a Screw,cap,socket Head, classified under FSC 5305, Screws. Status: active.
Key specifications for 5305-01-379-9947: Width Across Flats: 0.187 INCHES MINIMUM AND 0.190 INCHES MAXIMUM IN; Head Height: 0.244 INCHES MINIMUM AND 0.250 INCHES MAXIMUM IN; Fastener Length: 0.500 INCHES NOMINAL IN; Surface Treatment Document and Classification: MIL-C-13924 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL. 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.