The Bolt,close Tolerance, cataloged under National Stock Number 5306-00-765-4633, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Huck International, Inc. Government technical data includes 19 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-765-4633 |
| Primary Part Number | 51B464-4A23 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Huck International, Inc |
| Status | ACTIVE |
| Surface Finish | 32.0 MICROINCHES THREADS |
| Surface Finish | 32.0 MICROINCHES GRIP |
| Head Height | 0.125 INCHES NOMINAL IN |
| Fastener Length | 1.754 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-416 TY2 CL3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.316 INCHES MINIMUM IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.438 INCHES NOMINAL IN |
| Width Between Flats | 0.438 INCHES NOMINAL IN |
| Grip Diameter | 0.2485 INCHES MINIMUM AND 0.2495 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP E4340 OR STEEL COMP 8740 OR STEEL COMP 6150 OR STEEL COMP 4140 OVERALL |
| Thread Series Designator | UNF |
| 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 |
|---|---|
| 51B464-4A23 | Huck International, Inc (USA) |
| Reference | Meaning |
|---|---|
| 51B464-4A23 | C/1 Advisory reference — outside the item-of-supply concept Northrop Grumman Technical Services, Inc. Dba Defense Systems Sector |
| 51B464-4A23 | 3/9 Design control — primary reference Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems |
| 51B464-4A23 | 5/9 Secondary reference U.S. Government activity |
NSN 5306-00-765-4633 is a Bolt,close Tolerance, manufactured by Huck International, Inc, classified under FSC 5306, Bolts. Status: active.
NSN 5306-00-765-4633 has 1 manufacturer part number on file: 51B464-4A23 (Huck International, Inc).
Key specifications for 51B464-4A23: Surface Finish: 32.0 MICROINCHES THREADS; Surface Finish: 32.0 MICROINCHES GRIP; Head Height: 0.125 INCHES NOMINAL IN; Fastener Length: 1.754 INCHES NOMINAL IN. 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.