The Screw,cap,hexagon Head, cataloged under National Stock Number 5305-00-021-4124, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Lockheed Martin Corporation Div Rms - Mitchel Field. Government technical data includes 15 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-021-4124 |
| Primary Part Number | 419-551 |
| Item Name | Screw,cap,hexagon Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Lockheed Martin Corporation Div Rms - Mitchel Field |
| Status | ACTIVE |
| Head Height | 0.226 INCHES MINIMUM AND 0.243 INCHES MAXIMUM IN |
| Fastener Length | 3.000 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 1.000 INCHES MINIMUM AND 1.188 INCHES MAXIMUM IN |
| Material Document and Classification | 66 FED STD ALL MATERIAL RESPONSES OVERALL |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Width Between Flats | 0.551 INCHES MINIMUM AND 0.562 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Minimum Tensile Strength | 80000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 302 OR STEEL COMP 303 OR STEEL COMP 304 OR STEEL COMP 305 OR STEEL COMP 316 OVERALL |
| Thread Series Designator | UNF |
| 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 |
|---|---|
| 419-551 | Lockheed Martin Corporation Div Rms - Mitchel Field (USA) |
| Reference | Meaning |
|---|---|
| 5305000214124 | 6/9 Informative reference only E.c.a Etablissement Central Des Approvisionnements Des Forces Armees Royales |
| MS35308-370 | 3/2 Design control — primary reference U.S. Government activity |
| MS35308-370 | 5/9 Secondary reference U.S. Government activity |
NSN 5305-00-021-4124 is a Screw,cap,hexagon Head, manufactured by Lockheed Martin Corporation Div Rms - Mitchel Field, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-021-4124 has 1 manufacturer part number on file: 419-551 (Lockheed Martin Corporation Div Rms - Mitchel Field).
2 possible matches (shared part number, not a government interchangeability claim): 4720-00-470-2351, 1010-01-280-4206. Verify interchangeability with system specifications before substitution.
Key specifications for 419-551: Head Height: 0.226 INCHES MINIMUM AND 0.243 INCHES MAXIMUM IN; Fastener Length: 3.000 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 1.000 INCHES MINIMUM AND 1.188 INCHES MAXIMUM 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.