The Bolt,square Neck, cataloged under National Stock Number 5306-00-260-4643, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. Government technical data includes 19 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-260-4643 |
| Item Name | Bolt,square Neck |
| FSC / FSG | 5306 / 53 — Bolts |
| Status | ACTIVE |
| Neck Length | 0.375 INCHES MINIMUM AND 0.406 INCHES MAXIMUM IN |
| Head Height | 0.375 INCHES MINIMUM AND 0.406 INCHES MAXIMUM IN |
| Fastener Length | 8.000 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-Z-325,TY 2,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 1.750 INCHES MINIMUM IN |
| Hardness Rating | 95.0 ROCKWELL B MAXIMUM OVERALL |
| Nominal Thread Diameter | 0.750 INCHES IN |
| Head Style | BUTTON |
| Thread Direction | RIGHT-HAND |
| Nondefinitive Spec/std Data | 1 TYPE AND 1 STYLE |
| Neck Width | 0.741 INCHES MINIMUM AND 0.768 INCHES MAXIMUM IN |
| Surface Treatment | ZINC OVERALL |
| Minimum Tensile Strength | 55000 POUNDS PER SQUARE INCH LBS |
| Minimum Yield Strength | 29000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 10 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 1.469 INCHES MINIMUM AND 1.594 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 |
| Reference | Meaning |
|---|---|
| MS35751-197 | 3/2 Design control — primary reference U.S. Government activity |
| MS35751-197 | 5/9 Secondary reference U.S. Government activity |
NSN 5306-00-260-4643 is a Bolt,square Neck, classified under FSC 5306, Bolts. Status: active.
Key specifications for 5306-00-260-4643: Neck Length: 0.375 INCHES MINIMUM AND 0.406 INCHES MAXIMUM IN; Head Height: 0.375 INCHES MINIMUM AND 0.406 INCHES MAXIMUM IN; Fastener Length: 8.000 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-Z-325,TY 2,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL. 19 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.