The Screw,close Tolerance, cataloged under National Stock Number 5305-01-521-5145, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Heartland Precision Fasteners Inc. Government technical data includes 21 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-521-5145 |
| Primary Part Number | BACS12HW3AU8 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Heartland Precision Fasteners Inc |
| Status | ACTIVE |
| Spline Minor Diameter | 0.1105 INCHES MINIMUM AND 0.1205 INCHES MAXIMUM IN |
| Head Height | 0.122 INCHES MINIMUM AND 0.133 INCHES MAXIMUM IN |
| Fastener Length | 0.761 INCHES MINIMUM AND 0.791 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | AMS-QQ-P-35, TYPE II OR VIII ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.276 INCHES MINIMUM IN |
| Criticality Code Justification | AGAV |
| Material Document and Classification | AMS 5731 A286 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5732 A286 ASSN STD SINGLE MATERIAL RESPONSE OR AMS 5737 A286 ASSN STD SINGLE MATERIAL RESPONSE OR AMS 5853 A286 ASSN STD 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 CHAMFER |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.490 INCHES MINIMUM AND 0.520 INCHES MAXIMUM IN |
| Grip Diameter | 0.1890 INCHES MINIMUM AND 0.1895 INCHES MAXIMUM IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN OVERALL |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | TORX |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | IRON ALLOY 660 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.357 INCHES MINIMUM AND 0.373 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 | Y |
| Part Number | Manufacturer |
|---|---|
| BACS12HW3AU8 | Heartland Precision Fasteners Inc (USA) |
| BACS12HW3AU8 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| BACS12HW3AU8 | Pilgrim Screw Corp Dba Pilgrim Aerospace Fasteners Div Arizona (USA) |
| Reference | Meaning |
|---|---|
| BACS12HW3AU8 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-521-5145 is a Screw,close Tolerance, manufactured by Heartland Precision Fasteners Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-521-5145 has 3 manufacturer part numbers on file: BACS12HW3AU8 (Heartland Precision Fasteners Inc), BACS12HW3AU8 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), BACS12HW3AU8 (Pilgrim Screw Corp Dba Pilgrim Aerospace Fasteners Div Arizona).
Key specifications for BACS12HW3AU8: Spline Minor Diameter: 0.1105 INCHES MINIMUM AND 0.1205 INCHES MAXIMUM IN; Head Height: 0.122 INCHES MINIMUM AND 0.133 INCHES MAXIMUM IN; Fastener Length: 0.761 INCHES MINIMUM AND 0.791 INCHES MAXIMUM IN; Surface Treatment Document and Classification: AMS-QQ-P-35, TYPE II OR VIII ASSN STD SINGLE TREATMENT RESPONSE OVERALL. 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.