The Screw,assembled Washer, cataloged under National Stock Number 5305-00-042-5591, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is U S Army Tank Automotive Command Amsta-Im-Mm. Government technical data includes 18 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-042-5591 |
| Primary Part Number | 425591 |
| Item Name | Screw,assembled Washer |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | U S Army Tank Automotive Command Amsta-Im-Mm |
| Status | ACTIVE |
| Head Height | 0.208 INCHES MINIMUM AND 0.230 INCHES MAXIMUM IN |
| Fastener Length | 0.844 INCHES MINIMUM AND 0.875 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TY 1,CL 3 FED SPEC 1ST TREATMENT RESPONSE OR QQ-Z-325,TY 1,CL 3 FED SPEC 2ND TREATMENT RESPONSE OVERALL |
| Primary Washer Outside Diameter | 0.567 INCHES MINIMUM AND 0.590 INCHES MAXIMUM IN |
| Thread Length | 0.761 INCHES MINIMUM AND 0.844 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | HEXAGON |
| Primary Washer Style | FLAT EXTERNAL TEETH |
| Thread Direction | RIGHT-HAND |
| Primary Washer Material Thickness | 0.028 INCHES MINIMUM AND 0.034 INCHES MAXIMUM IN |
| Width Between Flats | 0.491 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OR ZINC OVERALL |
| Internal Drive Style | SLOT |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 1010 OR STEEL COMP 1020 OR STEEL COMP 1050 OVERALL |
| Thread Series Designator | UNF |
| Washer Quantity | 1 |
| 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 |
|---|---|
| 425591 PRIMARY | U S Army Tank Automotive Command Amsta-Im-Mm (USA) |
| Reference | Meaning |
|---|---|
| 5305000425591 | 6/9 Informative reference only E.c.a Etablissement Central Des Approvisionnements Des Forces Armees Royales |
NSN 5305-00-042-5591 is a Screw,assembled Washer, manufactured by U S Army Tank Automotive Command Amsta-Im-Mm, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-042-5591 has 1 manufacturer part number on file: 425591 (U S Army Tank Automotive Command Amsta-Im-Mm).
1 possible match (shared part number, not a government interchangeability claim): 5935-00-856-7920. Verify interchangeability with system specifications before substitution.
Key specifications for 425591: Head Height: 0.208 INCHES MINIMUM AND 0.230 INCHES MAXIMUM IN; Fastener Length: 0.844 INCHES MINIMUM AND 0.875 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC 1ST TREATMENT RESPONSE OR QQ-Z-325,TY 1,CL 3 FED SPEC 2ND TREATMENT RESPONSE OVERALL; Primary Washer Outside Diameter: 0.567 INCHES MINIMUM AND 0.590 INCHES MAXIMUM IN. 18 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.