The Screw,close Tolerance, cataloged under National Stock Number 5305-01-487-6866, 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 11 specifications, cited from the U.S. Government catalog. The record lists 17 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-487-6866 |
| Primary Part Number | ST3M557-4-12 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Fastener Length | 0.703 INCHES MINIMUM AND 0.750 INCHES MAXIMUM IN |
| Thread Length | 0.443 INCHES MINIMUM AND 0.510 INCHES MAXIMUM IN |
| Material Document and Classification | 23-118 FSCM 76301 MFR REF SINGLE MATERIAL RESPONSE OVERALL |
| Head Style | OVAL COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Internal Drive Style | HIGH-TORQUE |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.390 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 |
|---|---|
| ST3M557-4-12 | Heartland Precision Fasteners Inc (USA) |
| ST3M557-4-12 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| ST3M557-4-12 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| WC4027-4-12 | West Coast Aerospace, Inc. (USA) |
| HT4027-4-12 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| HT4027-4-12 | Howmet Global Fastening Systems Inc (USA) |
| ST3M557-4-12 | Ionics Ultrapure Water, Corp. Dba Apollo Ultrapure Water Systems, Inc. (USA) |
| 11923-4-12 | Macjewel Tool Developement Inc. Dba N/a Div N/a (USA) |
| HT4027-4-12 | Hi-Shear Corporation (USA) |
| ST3M557-4-12 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| ST3M557-4-12 | Twist Tite Mfg, Inc Dba Twist Tite Manufacturing Inc (USA) |
| ST3M557-4-12 PRIMARY | The Boeing Company Div Defense (USA) |
| ST3M557-4-12 | Linread Ltd (GBR) |
| ST3M557-4-12 | Saturn Fasteners Inc (USA) |
| HT4027-4-12 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| ST3M557-4-12 | Camcar Llc Div Camcar Llc (USA) |
| HT4027-4-12 | Huck International, Inc (USA) |
| Reference | Meaning |
|---|---|
| ST3M557-4-12 | 5/9 Secondary reference Swift Electric Welder Co |
| HT4027-4-12 | 5/2 Secondary reference U.S. Government activity |
| HT4027-4-12 | 5/2 Secondary reference U.S. Government activity |
NSN 5305-01-487-6866 is a Screw,close Tolerance, manufactured by The Boeing Company Div Defense, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-487-6866 has 17 manufacturer part numbers on file: ST3M557-4-12 (Heartland Precision Fasteners Inc), ST3M557-4-12 (Valley-Todeco, Inc. Dba Arconic Fastening Systems), ST3M557-4-12 (Fastener Innovation Technology, Inc. Dba F I T), WC4027-4-12 (West Coast Aerospace, Inc.), HT4027-4-12 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company) and 12 more.
Key specifications for ST3M557-4-12: Fastener Length: 0.703 INCHES MINIMUM AND 0.750 INCHES MAXIMUM IN; Thread Length: 0.443 INCHES MINIMUM AND 0.510 INCHES MAXIMUM IN; Material Document and Classification: 23-118 FSCM 76301 MFR REF SINGLE MATERIAL RESPONSE OVERALL; Head Style: OVAL COUNTERSUNK. 11 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.