The Screw,close Tolerance, cataloged under National Stock Number 5305-01-438-8279, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5305-01-438-8279 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Status | ACTIVE |
| Fastener Length | 2.753 INCHES MINIMUM AND 2.783 INCHES MAXIMUM IN |
| Thread Length | 0.743 INCHES MINIMUM AND 0.793 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.500 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.990 INCHES MINIMUM AND 2.010 INCHES MAXIMUM IN |
| Grip Diameter | 0.4985 INCHES MINIMUM AND 0.4995 INCHES MAXIMUM IN |
| Internal Drive Style | HIGH-TORQUE |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 101.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 20 |
| Material | STEEL COMP 4140 OR STEEL COMP E4340 OR STEEL COMP 8740 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 1.014 INCHES NOMINAL 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 |
|---|---|
| NAS1580A8H32 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-438-8279 is a Screw,close Tolerance, classified under FSC 5305, Screws. Status: active.
Key specifications for 5305-01-438-8279: Fastener Length: 2.753 INCHES MINIMUM AND 2.783 INCHES MAXIMUM IN; Thread Length: 0.743 INCHES MINIMUM AND 0.793 INCHES MAXIMUM IN; Nominal Thread Diameter: 0.500 INCHES IN; Head Style: FLAT COUNTERSUNK. 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.