The Bolt,close Tolerance, cataloged under National Stock Number 5306-01-063-3784, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company. Government technical data includes 19 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-01-063-3784 |
| Primary Part Number | MS21297-04021 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company |
| Status | ACTIVE |
| Surface Finish | 32.0 MICROINCHES GRIP |
| Surface Finish | 32.0 MICROINCHES BEARING SURFACE OF HEAD |
| Extended Washer Thickness | 0.026 INCHES MINIMUM AND 0.046 INCHES MAXIMUM IN |
| Head Height | 0.240 INCHES MINIMUM AND 0.260 INCHES MAXIMUM IN |
| Fastener Length | 1.807 INCHES MINIMUM AND 1.837 INCHES MAXIMUM IN |
| Extended Washer Diameter | 0.460 INCHES MINIMUM AND 0.470 INCHES MAXIMUM IN |
| Thread Length | 0.485 INCHES MINIMUM AND 0.535 INCHES MAXIMUM IN |
| Hardness Rating | 51.0 ROCKWELL C MINIMUM AND 54.0 ROCKWELL C MAXIMUM OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | SPLINE EXTENDED WASHER |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.302 INCHES MINIMUM AND 1.322 INCHES MAXIMUM IN |
| Width Between Flats | 0.235 INCHES MINIMUM AND 0.250 INCHES MAXIMUM IN |
| Grip Diameter | 0.2485 INCHES MINIMUM AND 0.2495 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP H11 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| 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 |
|---|---|
| MS21297-04021 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| MS21297-04021 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| MS21297-04021 | Huck International, Inc (USA) |
| Reference | Meaning |
|---|---|
| 5306PL1497619 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
| MS21297-04021 | 5/9 Secondary reference U.S. Government activity |
| MS21297-04021 | 3/2 Design control — primary reference U.S. Government activity |
| MS21297-04021 | 5/9 Secondary reference U.S. Government activity |
NSN 5306-01-063-3784 is a Bolt,close Tolerance, manufactured by Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-063-3784 has 3 manufacturer part numbers on file: MS21297-04021 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), MS21297-04021 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners), MS21297-04021 (Huck International, Inc).
Key specifications for MS21297-04021: Surface Finish: 32.0 MICROINCHES GRIP; Surface Finish: 32.0 MICROINCHES BEARING SURFACE OF HEAD; Extended Washer Thickness: 0.026 INCHES MINIMUM AND 0.046 INCHES MAXIMUM IN; Head Height: 0.240 INCHES MINIMUM AND 0.260 INCHES MAXIMUM 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.