The Screw,close Tolerance, cataloged under National Stock Number 5305-01-571-8407, 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 17 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-571-8407 |
| Primary Part Number | HT4027-4-26 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc |
| Status | ACTIVE |
| Fastener Length | 2.094 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.469 INCHES NOMINAL IN |
| Material Document and Classification | AMS5662 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.625 INCHES NOMINAL IN |
| Grip Diameter | 0.249 INCHES MINIMUM AND 0.250 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | HIGH-TORQUE |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | NICKEL ALLOY 718 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.389 INCHES MINIMUM AND 0.395 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 |
|---|---|
| HT4027-4-26 PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| HT4027-4-26 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| HT4027-4-26 PRIMARY | Hi-Shear Corporation (USA) |
| WC4027-4-26 | West Coast Aerospace, Inc. (USA) |
| Reference | Meaning |
|---|---|
| HT4027-4-266 | 5/9 Secondary reference Hi-Shear Corporation |
NSN 5305-01-571-8407 is a Screw,close Tolerance, manufactured by Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-571-8407 has 4 manufacturer part numbers on file: HT4027-4-26 (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), HT4027-4-26 (Sps Technologies, Llc Dba PB Fasteners), HT4027-4-26 (Hi-Shear Corporation), WC4027-4-26 (West Coast Aerospace, Inc.).
Key specifications for HT4027-4-26: Fastener Length: 2.094 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.469 INCHES NOMINAL IN; Material Document and Classification: AMS5662 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.