The Screw,close Tolerance, cataloged under National Stock Number 5305-01-507-4373, 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 21 specifications, cited from the U.S. Government catalog. The record lists 6 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-507-4373 |
| Primary Part Number | ST3M557-9D45 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Fastener Length | 3.7035 INCHES MINIMUM AND 3.7335 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.906 INCHES NOMINAL IN |
| Hole Configuration Style | ROUND |
| Material Document and Classification | AMS 5662 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.5625 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 2.8025 INCHES MINIMUM AND 2.8225 INCHES MAXIMUM IN |
| Grip Diameter | 0.5610 INCHES MINIMUM AND 0.5615 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 | 18 |
| Material | NICKEL ALLOY 718 OVERALL |
| Hole Quantity | 1 |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Hole Type | DRILLED |
| Hole Diameter | 0.141 INCHES MINIMUM AND 0.146 INCHES MAXIMUM IN |
| Head Diameter | 0.838 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 |
|---|---|
| HT4027-9D45 | Hi-Shear Corporation (USA) |
| ST3M557-9D45 | Houston Precision Fasteners I Lp (USA) |
| ST3M557-9D45 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| HT4027-9D45 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| HT4027-9D45 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| ST3M557-9D45 PRIMARY | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| HT4027-9D45 | 5/2 Secondary reference U.S. Government activity |
| ST3M557 | D/9 Drawing number reference only The Boeing Company Div Defense |
NSN 5305-01-507-4373 is a Screw,close Tolerance, manufactured by The Boeing Company Div Defense, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-507-4373 has 6 manufacturer part numbers on file: HT4027-9D45 (Hi-Shear Corporation), ST3M557-9D45 (Houston Precision Fasteners I Lp), ST3M557-9D45 (Fastener Innovation Technology, Inc. Dba F I T), HT4027-9D45 (Sps Technologies, Llc Dba PB Fasteners), HT4027-9D45 (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc) and 1 more.
Key specifications for ST3M557-9D45: Fastener Length: 3.7035 INCHES MINIMUM AND 3.7335 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.906 INCHES NOMINAL IN; Hole Configuration Style: ROUND. 21 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.