The Screw,close Tolerance, cataloged under National Stock Number 5305-01-593-4785, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company Div Defense. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-593-4785 |
| Primary Part Number | ST3M454-8L13 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Fastener Length | 1.593 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | AMS 2700 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.781 INCHES NOMINAL IN |
| Material Document and Classification | AMS 5629 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.500 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.802 INCHES MINIMUM AND 0.822 INCHES MAXIMUM IN |
| Grip Diameter | 0.499 INCHES NOMINAL IN |
| Surface Treatment | PASSIVATE OVERALL |
| 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 XM-13 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 1.007 INCHES MINIMUM AND 1.017 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 |
| Part Number | Manufacturer |
|---|---|
| HT4025L8-13 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| ST3M454-8L13 PRIMARY | The Boeing Company Div Defense (USA) |
| HT4025L8-13 | Howmet Global Fastening Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| HT4025L8-13 | 5/9 Secondary reference Sps Technologies Inc |
NSN 5305-01-593-4785 is a Screw,close Tolerance, manufactured by The Boeing Company Div Defense, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-593-4785 has 3 manufacturer part numbers on file: HT4025L8-13 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), ST3M454-8L13 (The Boeing Company Div Defense), HT4025L8-13 (Howmet Global Fastening Systems Inc).
Key specifications for ST3M454-8L13: Fastener Length: 1.593 INCHES NOMINAL IN; Surface Treatment Document and Classification: AMS 2700 ASSN STD SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.781 INCHES NOMINAL IN; Material Document and Classification: AMS 5629 ASSN STD SINGLE MATERIAL RESPONSE OVERALL. 17 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.