The Screw,close Tolerance, cataloged under National Stock Number 5305-01-512-7265, 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 9 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-512-7265 |
| Primary Part Number | ST3M557-4-8 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Fastener Length | 0.969 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.469 INCHES NOMINAL IN |
| Material Document and Classification | AMS 5662 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.490 INCHES MINIMUM AND 0.510 INCHES MAXIMUM IN |
| Grip Diameter | 0.2490 INCHES MINIMUM AND 0.2495 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 | 28 |
| Material | NICKEL ALLOY 718 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.3898 INCHES MINIMUM AND 0.3948 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 |
|---|---|
| HT4027-4-8 | Hi-Shear Corporation (USA) |
| HT4027-4-8 | Howmet Global Fastening Systems Inc (USA) |
| 11923-4-8 | Reid Products Inc. Dba Reid Products Inc (USA) |
| WC4027-4-8 | West Coast Aerospace, Inc. (USA) |
| ST3M557-4-8 PRIMARY | The Boeing Company Div Defense (USA) |
| ST3M557-4-8 | Twist Tite Mfg, Inc Dba Twist Tite Manufacturing Inc (USA) |
| ST3M557-4-8 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| HT4027-4-8 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| HT4027-4-8 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| Reference | Meaning |
|---|---|
| ST3M557 | D/9 Drawing number reference only The Boeing Company Div Defense |
| HT4027-4-8 | 5/9 Secondary reference Sps Technologies Inc |
NSN 5305-01-512-7265 is a Screw,close Tolerance, manufactured by The Boeing Company Div Defense, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-512-7265 has 9 manufacturer part numbers on file: HT4027-4-8 (Hi-Shear Corporation), HT4027-4-8 (Howmet Global Fastening Systems Inc), 11923-4-8 (Reid Products Inc. Dba Reid Products Inc), WC4027-4-8 (West Coast Aerospace, Inc.), ST3M557-4-8 (The Boeing Company Div Defense) and 4 more.
Key specifications for ST3M557-4-8: Fastener Length: 0.969 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.469 INCHES NOMINAL IN; Material Document and Classification: AMS 5662 ASSN STD SINGLE MATERIAL RESPONSE OVERALL. 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.