The Bolt,close Tolerance, cataloged under National Stock Number 5306-00-321-9271, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Hi-Shear Corporation. Government technical data includes 13 specifications, cited from the U.S. Government catalog. The record lists 8 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5306-00-321-9271 |
| Primary Part Number | MB61-5-10 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Hi-Shear Corporation |
| Status | ACTIVE |
| Head Height | 0.177 INCHES MINIMUM AND 0.197 INCHES MAXIMUM IN |
| Fastener Length | 1.076 INCHES MINIMUM AND 1.123 INCHES MAXIMUM IN |
| Thread Length | 0.441 INCHES MINIMUM AND 0.508 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | DOUBLE HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.615 INCHES MINIMUM AND 0.635 INCHES MAXIMUM IN |
| Width Between Flats | 0.492 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN |
| Grip Diameter | 0.3115 INCHES MINIMUM AND 0.3120 INCHES MAXIMUM IN |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL CORROSION RESISTING 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 |
|---|---|
| MB61-5-10 PRIMARY | Hi-Shear Corporation (USA) |
| GS1016-5-10 | B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace (USA) |
| 109453-5-10 PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| ST3M453-5-10 | Howmet Global Fastening Systems Inc (USA) |
| VAL23029-5-10 PRIMARY | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| ST3M453-5-10 PRIMARY | The Boeing Company Div Defense (USA) |
| 11825-5-10 | Reid Products Inc. Dba Reid Products Inc (USA) |
| ST3M453-5-10 | Heartland Precision Fasteners Inc (USA) |
| Reference | Meaning |
|---|---|
| MB61-5-10 | 5/9 Secondary reference Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc |
| 109453-5-10 | 5/9 Secondary reference Sps Technologies Inc |
| BM17019-5-10 | 5/9 Secondary reference U.S. Government activity |
| US3204-5-10 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5306-00-321-9271 is a Bolt,close Tolerance, manufactured by Hi-Shear Corporation, classified under FSC 5306, Bolts. Status: active.
NSN 5306-00-321-9271 has 8 manufacturer part numbers on file: MB61-5-10 (Hi-Shear Corporation), GS1016-5-10 (B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace), 109453-5-10 (Sps Technologies, Llc Dba PB Fasteners), ST3M453-5-10 (Howmet Global Fastening Systems Inc), VAL23029-5-10 (Valley-Todeco, Inc. Dba Arconic Fastening Systems) and 3 more.
Key specifications for MB61-5-10: Head Height: 0.177 INCHES MINIMUM AND 0.197 INCHES MAXIMUM IN; Fastener Length: 1.076 INCHES MINIMUM AND 1.123 INCHES MAXIMUM IN; Thread Length: 0.441 INCHES MINIMUM AND 0.508 INCHES MAXIMUM IN; Nominal Thread Diameter: 0.312 INCHES IN. 13 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.