The Bolt,close Tolerance, cataloged under National Stock Number 5306-01-179-0902, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 2 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5306-01-179-0902 |
| Primary Part Number | HS6051-6-21 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok |
| Status | ACTIVE |
| Head Height | 0.378 INCHES MINIMUM AND 0.398 INCHES MAXIMUM IN |
| Fastener Length | 2.312 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | MIL-C-6887,TY2,CL2 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 1.000 INCHES NOMINAL IN |
| Material Document and Classification | AMS5514 ASSN STD SINGLE MATERIAL RESPONSE OR AMS6532 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | DOUBLE HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.313 INCHES NOMINAL IN |
| Width Between Flats | 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN |
| Grip Diameter | 0.343 INCHES MINIMUM AND 0.353 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Minimum Tensile Strength | 280000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 305 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 |
|---|---|
| HS6051-6-21 PRIMARY | Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok (USA) |
| SLB361-6-21 | Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok (USA) |
| Reference | Meaning |
|---|---|
| HS6051-6-21 | 7/2 Vendor item drawing reference The Boeing Company |
| HS6051-6-21 | 5/9 Secondary reference Mcdonnell Douglas Helicopter Co Inc |
NSN 5306-01-179-0902 is a Bolt,close Tolerance, manufactured by Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-179-0902 has 2 manufacturer part numbers on file: HS6051-6-21 (Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok), SLB361-6-21 (Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok).
Key specifications for HS6051-6-21: Head Height: 0.378 INCHES MINIMUM AND 0.398 INCHES MAXIMUM IN; Fastener Length: 2.312 INCHES NOMINAL IN; Surface Treatment Document and Classification: MIL-C-6887,TY2,CL2 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 1.000 INCHES NOMINAL IN. 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.