The Screw,shoulder, cataloged under National Stock Number 5305-01-239-0642, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Hi-Shear Corporation. Government technical data includes 19 specifications, cited from the U.S. Government catalog. The record lists 4 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-239-0642 |
| Primary Part Number | HT4020-4-19Y |
| Item Name | Screw,shoulder |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Hi-Shear Corporation |
| Status | ACTIVE |
| Head Height | 0.058 INCHES MINIMUM AND 0.060 INCHES MAXIMUM IN |
| Fastener Length | 1.640 INCHES MINIMUM AND 1.688 INCHES MAXIMUM IN |
| Shoulder Length | 1.178 INCHES MINIMUM AND 1.198 INCHES MAXIMUM FIRST SHOULDER IN |
| Shoulder Diameter | 0.2802 INCHES MINIMUM AND 0.2807 INCHES MAXIMUM FIRST SHOULDER IN |
| Thread Length | 0.442 INCHES MINIMUM AND 0.510 INCHES MAXIMUM IN |
| Shoulder Shape | ROUND FIRST SHOULDER |
| Material Document and Classification | AMS5629 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK UNDERCUT |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | PASSIVATE OVERALL |
| Minimum Tensile Strength | 125000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HIGH-TORQUE |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP XM-13 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.501 INCHES MINIMUM AND 0.506 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 |
|---|---|
| HT4020-4-19Y PRIMARY | Hi-Shear Corporation (USA) |
| HT4020-4-19Y PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| 3M902C4-19D | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| 11879C4-19D | Reid Products Inc. Dba Reid Products Inc (USA) |
| Reference | Meaning |
|---|---|
| HT4020-4-19Y | 5/9 Secondary reference U.S. Government activity |
| HT4020-4-19Y | C/1 Advisory reference — outside the item-of-supply concept Howmet Global Fastening Systems Inc |
| 3M902C4-19D | 5/2 Secondary reference U.S. Government activity |
| HT4020-4-19Y | C/1 Advisory reference — outside the item-of-supply concept Huck International, Inc |
| HT4020-4-19Y | 3/2 Design control — primary reference U.S. Government activity |
| HT4020-4-19Y | 5/9 Secondary reference U.S. Government activity |
| 3M902C4-19D | 7/2 Vendor item drawing reference The Boeing Company Div Defense |
NSN 5305-01-239-0642 is a Screw,shoulder, manufactured by Hi-Shear Corporation, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-239-0642 has 4 manufacturer part numbers on file: HT4020-4-19Y (Hi-Shear Corporation), HT4020-4-19Y (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), 3M902C4-19D (Fastener Innovation Technology, Inc. Dba F I T), 11879C4-19D (Reid Products Inc. Dba Reid Products Inc).
Key specifications for HT4020-4-19Y: Head Height: 0.058 INCHES MINIMUM AND 0.060 INCHES MAXIMUM IN; Fastener Length: 1.640 INCHES MINIMUM AND 1.688 INCHES MAXIMUM IN; Shoulder Length: 1.178 INCHES MINIMUM AND 1.198 INCHES MAXIMUM FIRST SHOULDER IN; Shoulder Diameter: 0.2802 INCHES MINIMUM AND 0.2807 INCHES MAXIMUM FIRST SHOULDER 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.