The Screw,close Tolerance, cataloged under National Stock Number 5305-01-563-3863, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company Div Defense. Government technical data includes 15 specifications, cited from the U.S. Government catalog. The record lists 18 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-563-3863 |
| Primary Part Number | ST3M557-6-13 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Fastener Length | 1.447 INCHES NOMINAL IN |
| Thread Length | 0.641 INCHES NOMINAL IN |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | OVAL COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.615 INCHES MINIMUM AND 0.635 INCHES MAXIMUM IN |
| Grip Diameter | 0.374 INCHES NOMINAL 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 | 24 |
| Material | NICKEL ALLOY 718 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.564 INCHES NOMINAL 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 |
|---|---|
| WC4027-6-13 | West Coast Aerospace, Inc. (USA) |
| HT4027-6-13 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| ST3M557-6-13 | Heartland Precision Fasteners Inc (USA) |
| HT4027-6-13 | Apex Engineering Products Corp (USA) |
| ST3M557-6-13 | Camcar Llc Div Camcar Llc (USA) |
| HT4027-6-13 | Hi-Shear Corporation (USA) |
| ST3M557-6-13 | Saturn Fasteners Inc (USA) |
| ST3M557-6-13 | Linread Ltd (GBR) |
| HT4027-6-13 | Huck International, Inc (USA) |
| ST3M557-6-13 | Reid Products Inc. Dba Reid Products Inc (USA) |
| HT4027-6-13 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| HT4027-6-13 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| ST3M557-6-13 | Houston Precision Fasteners I Lp (USA) |
| ST3M557-6-13 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| ST3M557-6-13 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| HT4027-6-13 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| 11923-6-13 | Reid Products Inc. Dba Reid Products Inc (USA) |
| ST3M557-6-13 PRIMARY | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| HT4027-6-13 | 5/2 Secondary reference U.S. Government activity |
| HT4027-6-13 | 5/2 Secondary reference U.S. Government activity |
| HT4027-6-13 | 5/9 Secondary reference Sps Technologies Inc |
| ST3M557-6-13 | 5/9 Secondary reference Swift Ohio Corp |
NSN 5305-01-563-3863 is a Screw,close Tolerance, manufactured by The Boeing Company Div Defense, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-563-3863 has 18 manufacturer part numbers on file: WC4027-6-13 (West Coast Aerospace, Inc.), HT4027-6-13 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners), ST3M557-6-13 (Heartland Precision Fasteners Inc), HT4027-6-13 (Apex Engineering Products Corp), ST3M557-6-13 (Camcar Llc Div Camcar Llc) and 13 more.
Key specifications for ST3M557-6-13: Fastener Length: 1.447 INCHES NOMINAL IN; Thread Length: 0.641 INCHES NOMINAL IN; Nominal Thread Diameter: 0.375 INCHES IN; Head Style: OVAL COUNTERSUNK. 15 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.