The Screw,close Tolerance, cataloged under National Stock Number 5305-01-666-8495, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. Government technical data includes 15 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5305-01-666-8495 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Status | ACTIVE |
| Head Height | 0.176 INCHES MINIMUM AND 0.188 INCHES MAXIMUM IN |
| Fastener Length | 0.861 INCHES MINIMUM AND 0.891 INCHES MAXIMUM IN |
| Thread Length | 0.501 INCHES NOMINAL IN |
| Nominal Thread Diameter | 0.3125 INCHES IN |
| Head Style | FLAT FILLISTER |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.365 INCHES MINIMUM AND 0.385 INCHES MAXIMUM IN |
| Grip Diameter | 0.3110 INCHES MINIMUM AND 0.3120 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Internal Drive Style | HIGH-TORQUE |
| 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 | 0.597 INCHES MINIMUM AND 0.612 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 |
|---|---|
| NAS1578A5H6 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-666-8495 is a Screw,close Tolerance, classified under FSC 5305, Screws. Status: active.
Key specifications for 5305-01-666-8495: Head Height: 0.176 INCHES MINIMUM AND 0.188 INCHES MAXIMUM IN; Fastener Length: 0.861 INCHES MINIMUM AND 0.891 INCHES MAXIMUM IN; Thread Length: 0.501 INCHES NOMINAL IN; Nominal Thread Diameter: 0.3125 INCHES IN. 15 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.