The Bolt,shoulder, cataloged under National Stock Number 5306-01-045-5558, 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 15 specifications, cited from the U.S. Government catalog. The record lists 7 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-01-045-5558 |
| Primary Part Number | MB89-4-25 |
| Item Name | Bolt,shoulder |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Hi-Shear Corporation |
| Status | ACTIVE |
| Head Height | 0.154 INCHES MINIMUM AND 0.174 INCHES MAXIMUM IN |
| Fastener Length | 1.943 INCHES MINIMUM AND 1.990 INCHES MAXIMUM IN |
| Shoulder Length | 1.553 INCHES MINIMUM AND 1.373 INCHES MAXIMUM FIRST SHOULDER IN |
| Shoulder Diameter | 0.2802 INCHES MINIMUM AND 0.2807 INCHES MAXIMUM FIRST SHOULDER IN |
| Thread Length | 0.371 INCHES MINIMUM AND 0.438 INCHES MAXIMUM IN |
| Shoulder Shape | ROUND FIRST SHOULDER |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | DOUBLE HEXAGON |
| Thread Direction | RIGHT-HAND |
| Specification/standard Data | 76301-ST3-507 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Width Between Flats | 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL 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 |
|---|---|
| MB89-4-25 | Hi-Shear Corporation (USA) |
| ST3M507-4-25 | Howmet Global Fastening Systems Inc (USA) |
| BM17019-4-24Y | Huck International, Inc (USA) |
| MB89-4-25 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| ST3M507-4-25 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| ST3M507-4-25 | Heartland Precision Fasteners Inc (USA) |
| VAL23608-4-25 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| Reference | Meaning |
|---|---|
| BM17019-4-25Y | 5/9 Secondary reference U.S. Government activity |
| 109453-4-25Y | 5/9 Secondary reference Sps Technologies, Llc Dba PB Fasteners |
| BM17019-4-25Y | C/1 Advisory reference — outside the item-of-supply concept Huck International, Inc |
| VS3038-4-25 | 5/9 Secondary reference U.S. Government activity |
| ST3M507-4-25 | 5/9 Secondary reference Sps Technologies Inc |
| ST3M507-4-25 | 3/9 Design control — primary reference The Boeing Company Div Defense |
| 109453-4-25Y | 5/2 Secondary reference U.S. Government activity |
NSN 5306-01-045-5558 is a Bolt,shoulder, manufactured by Hi-Shear Corporation, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-045-5558 has 7 manufacturer part numbers on file: MB89-4-25 (Hi-Shear Corporation), ST3M507-4-25 (Howmet Global Fastening Systems Inc), BM17019-4-24Y (Huck International, Inc), MB89-4-25 (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), ST3M507-4-25 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners) and 2 more.
Key specifications for MB89-4-25: Head Height: 0.154 INCHES MINIMUM AND 0.174 INCHES MAXIMUM IN; Fastener Length: 1.943 INCHES MINIMUM AND 1.990 INCHES MAXIMUM IN; Shoulder Length: 1.553 INCHES MINIMUM AND 1.373 INCHES MAXIMUM FIRST SHOULDER IN; Shoulder Diameter: 0.2802 INCHES MINIMUM AND 0.2807 INCHES MAXIMUM FIRST SHOULDER IN. 15 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.