The Screw,close Tolerance, cataloged under National Stock Number 5305-01-591-0128, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Huck International, Inc. Government technical data includes 23 specifications, cited from the U.S. Government catalog. The record lists 15 manufacturer part numbers 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-591-0128 |
| Primary Part Number | HT4027-3D6 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Huck International, Inc |
| Status | ACTIVE |
| Head Height | 0.013 INCHES MAXIMUM IN |
| Point Length | 0.039 INCHES NOMINAL IN |
| Fastener Length | 0.579 INCHES MINIMUM AND 0.609 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | AMS 2700 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.406 INCHES NOMINAL IN |
| Shank Unthreaded Hole Diameter | 0.070 INCHES MINIMUM AND 0.075 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | AMS 5662 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Point Chamfer Angle | 45.0 DEGREES NOMINAL |
| Nominal Thread Diameter | 0.190 INCHES IN |
| Head Style | FILLISTER COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Point Style | FLAT |
| Grip Length | 0.188 INCHES NOMINAL IN |
| Grip Diameter | 0.189 INCHES MINIMUM AND 0.190 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | HIGH-TORQUE |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 101.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | NICKEL ALLOY 718 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 0.473 INCHES MINIMUM AND 0.483 INCHES MAXIMUM FIRST HOLE IN |
| Head Diameter | 0.297 INCHES MINIMUM AND 0.302 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 |
|---|---|
| HT4027-3D6 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| ST3M557-3D6 | Saturn Fasteners Inc (USA) |
| HT4027-3D6 PRIMARY | Huck International, Inc (USA) |
| ST3M557-3D6 | Linread Ltd (GBR) |
| HT4027-3D6 PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| 11923-3D6 | Reid Products Inc. Dba Reid Products Inc (USA) |
| ST3M557-3D6 | Heartland Precision Fasteners Inc (USA) |
| ST3M447-3D6 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| ST3M557-3D6 | Houston Precision Fasteners I Lp (USA) |
| WC4027-3D6 | West Coast Aerospace, Inc. (USA) |
| ST3M557-3D6 | Camcar Llc Div Camcar Llc (USA) |
| HT4027-3D6 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| HT4027-3D6 | Hi-Shear Corporation (USA) |
| HT4027-3D6 PRIMARY | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| HT4027-3D6 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| Reference | Meaning |
|---|---|
| ST3M557-3D6 | 7/2 Vendor item drawing reference The Boeing Company Div Defense |
| HT4027-3D6 | 5/2 Secondary reference U.S. Government activity |
| HT4027-3D6 | 5/2 Secondary reference U.S. Government activity |
NSN 5305-01-591-0128 is a Screw,close Tolerance, manufactured by Huck International, Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-591-0128 has 15 manufacturer part numbers on file: HT4027-3D6 (Sps Technologies, Llc Dba PB Fasteners), ST3M557-3D6 (Saturn Fasteners Inc), HT4027-3D6 (Huck International, Inc), ST3M557-3D6 (Linread Ltd), HT4027-3D6 (Howmet Global Fastening Systems Inc) and 10 more.
Key specifications for HT4027-3D6: Head Height: 0.013 INCHES MAXIMUM IN; Point Length: 0.039 INCHES NOMINAL IN; Fastener Length: 0.579 INCHES MINIMUM AND 0.609 INCHES MAXIMUM IN; Surface Treatment Document and Classification: AMS 2700 ASSN STD SINGLE TREATMENT RESPONSE OVERALL. 23 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.