The Screw,close Tolerance, cataloged under National Stock Number 5305-01-477-5625, 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 17 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-477-5625 |
| Primary Part Number | HT4020-6-18A |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Huck International, Inc |
| Status | ACTIVE |
| Head Height | 0.115 INCHES MINIMUM AND 0.117 INCHES MAXIMUM IN |
| Fastener Length | 1.750 INCHES MINIMUM AND 1.797 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.641 INCHES NOMINAL IN |
| Criticality Code Justification | AGAV |
| Material Document and Classification | AMS 5629 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | FLAT COUNTERSUNK UNDERCUT |
| Thread Direction | RIGHT-HAND |
| 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 | 24 |
| Material | STEEL COMP XM-13 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.756 INCHES MINIMUM AND 0.760 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 | Y |
| Part Number | Manufacturer |
|---|---|
| HT4020-6-18A PRIMARY | Huck International, Inc (USA) |
| ST3M652C6-18A | Houston Precision Fasteners I Lp (USA) |
| ST3M652C6-18A PRIMARY | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| ST3M652C6-18A PRIMARY | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| HT4020-6-18A PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| ST3M652C6-18A PRIMARY | Heartland Precision Fasteners Inc (USA) |
| HT4020-6-18A PRIMARY | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| HT4020-6-18A PRIMARY | Hi-Shear Corporation (USA) |
| HT4020-6-18A PRIMARY | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| WC4020-6-18A | West Coast Aerospace, Inc. (USA) |
| HT4020-6-18A PRIMARY | Sps Technologies Ltd, Tj Brooks Division (GBR) |
| HT4020-6-18A PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| HT4020-6-18A PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| 11925C6-18A | Reid Products Inc. Dba Reid Products Inc (USA) |
| ST3M652C6-18A | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| HT4020-6-18A | 3/2 Design control — primary reference U.S. Government activity |
| HT4020-6-18A | 3/2 Design control — primary reference U.S. Government activity |
| HT4020-6-18A | 5/9 Secondary reference Sps Technologies Inc |
NSN 5305-01-477-5625 is a Screw,close Tolerance, manufactured by Huck International, Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-477-5625 has 15 manufacturer part numbers on file: HT4020-6-18A (Huck International, Inc), ST3M652C6-18A (Houston Precision Fasteners I Lp), ST3M652C6-18A (Fastener Innovation Technology, Inc. Dba F I T), ST3M652C6-18A (Valley-Todeco, Inc. Dba Arconic Fastening Systems), HT4020-6-18A (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc) and 10 more.
Key specifications for HT4020-6-18A: Head Height: 0.115 INCHES MINIMUM AND 0.117 INCHES MAXIMUM IN; Fastener Length: 1.750 INCHES MINIMUM AND 1.797 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.641 INCHES NOMINAL IN. 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.