The Screw,shoulder, cataloged under National Stock Number 5305-01-239-0643, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc. Government technical data includes 19 specifications, cited from the U.S. Government catalog. The record lists 5 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 6 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-239-0643 |
| Primary Part Number | HT4020-4-17AY |
| Item Name | Screw,shoulder |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc |
| Status | ACTIVE |
| Head Height | 0.058 INCHES MINIMUM AND 0.060 INCHES MAXIMUM IN |
| Fastener Length | 1.515 INCHES MINIMUM AND 1.562 INCHES MAXIMUM IN |
| Shoulder Length | 1.052 INCHES MINIMUM AND 1.072 INCHES MAXIMUM FIRST SHOULDER IN |
| Shoulder Diameter | 0.2802 INCHES MINIMUM AND 0.2807 INCHES MAXIMUM FIRST SHOULDER IN |
| Thread Length | 0.443 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 |
|---|---|
| 3M902C4-17A | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| 11879C4-17A | Reid Products Inc. Dba Reid Products Inc (USA) |
| HT4020-4-17AY PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| HT4020-4-17AY PRIMARY | Hi-Shear Corporation (USA) |
| 3M902C4-17A | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| HT4020-4-17AY | C/1 Advisory reference — outside the item-of-supply concept Howmet Global Fastening Systems Inc |
| HT4020-4-17AY | 5/9 Secondary reference U.S. Government activity |
| 3M902C4-17A | 5/2 Secondary reference U.S. Government activity |
| HT4020-4-17AY | 3/2 Design control — primary reference U.S. Government activity |
| HT4020-4-17AY | 5/9 Secondary reference U.S. Government activity |
| HT4020-4-17AY | C/1 Advisory reference — outside the item-of-supply concept Huck International, Inc |
NSN 5305-01-239-0643 is a Screw,shoulder, manufactured by Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-239-0643 has 5 manufacturer part numbers on file: 3M902C4-17A (Fastener Innovation Technology, Inc. Dba F I T), 11879C4-17A (Reid Products Inc. Dba Reid Products Inc), HT4020-4-17AY (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), HT4020-4-17AY (Hi-Shear Corporation), 3M902C4-17A (The Boeing Company Div Defense).
Key specifications for HT4020-4-17AY: Head Height: 0.058 INCHES MINIMUM AND 0.060 INCHES MAXIMUM IN; Fastener Length: 1.515 INCHES MINIMUM AND 1.562 INCHES MAXIMUM IN; Shoulder Length: 1.052 INCHES MINIMUM AND 1.072 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.