The Screw,close Tolerance, cataloged under National Stock Number 5305-01-443-6979, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. Government technical data includes 19 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-443-6979 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Status | ACTIVE |
| Head Height | 0.070 INCHES NOMINAL IN |
| Fastener Length | 1.626 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-416,TY2,CL2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.501 INCHES NOMINAL IN |
| Material Document and Classification | MIL-S-5626 MIL SPEC SINGLE MATERIAL RESPONSE OR MIL-S-5000 MIL SPEC SINGLE MATERIAL RESPONSE OR MIL-S-6049 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.125 INCHES NOMINAL IN |
| Grip Diameter | 0.3110 INCHES MINIMUM AND 0.3120 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Minimum Tensile Strength | 160000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | OFFSET CRUCIFORM (TORQUE SET) |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 101.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 4140 OR STEEL COMP 4340 OR STEEL COMP 8740 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.4289 INCHES MINIMUM 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 |
|---|---|
| NAS1581F5R18 | 3/2 Design control — primary reference U.S. Government activity |
| NAS1581A5R18 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
NSN 5305-01-443-6979 is a Screw,close Tolerance, classified under FSC 5305, Screws. Status: active.
Key specifications for 5305-01-443-6979: Head Height: 0.070 INCHES NOMINAL IN; Fastener Length: 1.626 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-416,TY2,CL2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.501 INCHES NOMINAL IN. 19 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.