The Screw,close Tolerance, cataloged under National Stock Number 5305-01-521-9583, 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 17 specifications, cited from the U.S. Government catalog. The record lists 10 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-521-9583 |
| Primary Part Number | ST3M557-3-17 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Fastener Length | 1.468 INCHES NOMINAL IN |
| Thread Length | 0.313 INCHES NOMINAL IN |
| Material Document and Classification | BPS-F-69 MFR REF SINGLE MATERIAL RESPONSE OVERALL |
| Spline Major Diameter | 0.154 INCHES MINIMUM AND 0.156 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.190 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.062 INCHES NOMINAL IN |
| Grip Diameter | 0.1885 INCHES MINIMUM AND 0.1895 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | TORX |
| Countersink Angle | 99.0 DEGREES NOMINAL 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) |
| Head Diameter | 0.293 INCHES MINIMUM AND 0.301 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 |
|---|---|
| ST3M557-3-17 PRIMARY | The Boeing Company Div Defense (USA) |
| ST3M557-3-17 | West Coast Aerospace, Inc. (USA) |
| ST3M557-3-17 | Twist Tite Mfg, Inc Dba Twist Tite Manufacturing Inc (USA) |
| HT4027-3-17 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| ST3M557-3-17 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| ST3M557-3-17 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| ST3M557-3-17 | Howmet Global Fastening Systems Inc (USA) |
| ST3M557-3-17 | Hi-Shear Corporation (USA) |
| HT4027-3-17 | West Coast Aerospace, Inc. (USA) |
| HT4027-3-17 | Kvh Industries Inc (USA) |
| Reference | Meaning |
|---|---|
| ST3M557 | D/9 Drawing number reference only The Boeing Company Div Defense |
| HT4027-3-17 | 5/2 Secondary reference U.S. Government activity |
| ST3M557-3-17 | 5/2 Secondary reference U.S. Government activity |
| HT4027-3-17 | 5/9 Secondary reference Sps Technologies, Llc Dba PB Fasteners |
| HT4027-3-17 | 5/9 Secondary reference Howmet Global Fastening Systems Inc |
NSN 5305-01-521-9583 is a Screw,close Tolerance, manufactured by The Boeing Company Div Defense, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-521-9583 has 10 manufacturer part numbers on file: ST3M557-3-17 (The Boeing Company Div Defense), ST3M557-3-17 (West Coast Aerospace, Inc.), ST3M557-3-17 (Twist Tite Mfg, Inc Dba Twist Tite Manufacturing Inc), HT4027-3-17 (Fastener Innovation Technology, Inc. Dba F I T), ST3M557-3-17 (Fastener Innovation Technology, Inc. Dba F I T) and 5 more.
Key specifications for ST3M557-3-17: Fastener Length: 1.468 INCHES NOMINAL IN; Thread Length: 0.313 INCHES NOMINAL IN; Material Document and Classification: BPS-F-69 MFR REF SINGLE MATERIAL RESPONSE OVERALL; Spline Major Diameter: 0.154 INCHES MINIMUM AND 0.156 INCHES MAXIMUM 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.