The Bolt,close Tolerance, cataloged under National Stock Number 5306-00-326-4625, 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 20 specifications, cited from the U.S. Government catalog. The record lists 16 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through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5306-00-326-4625 |
| Primary Part Number | MB84-6H23 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Hi-Shear Corporation |
| Status | ACTIVE |
| Extended Washer Thickness | 0.081 INCHES MINIMUM AND 0.101 INCHES MAXIMUM IN |
| Head Height | 0.378 INCHES MINIMUM AND 0.398 INCHES MAXIMUM IN |
| Fastener Length | 2.037 INCHES MINIMUM AND 2.067 INCHES MAXIMUM IN |
| Extended Washer Diameter | 0.639 INCHES MINIMUM AND 0.649 INCHES MAXIMUM IN |
| Thread Length | 0.589 INCHES MINIMUM AND 0.639 INCHES MAXIMUM IN |
| Hole Configuration Style | HEXAGON LONGITUDINAL HOLE |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | DOUBLE HEXAGON W/HOLE |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.428 INCHES MINIMUM AND 1.448 INCHES MAXIMUM IN |
| Width Between Flats | 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN |
| Grip Diameter | 0.3740 INCHES MINIMUM AND 0.3745 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Hole Quantity | 4 |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Hole Type | DRILLED |
| Hole Diameter | 0.055 INCHES NOMINAL IN |
| 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 |
|---|---|
| ST3M571-6H23 | Heartland Precision Fasteners Inc (USA) |
| MB84-6H23 PRIMARY | Hi-Shear Corporation (USA) |
| BM3326-6H23 PRIMARY | Huck International, Inc (USA) |
| VS3060-6H23 PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| GS1030-6H23 | B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace (USA) |
| AIC752-6H23 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| ST3M571-6H23 PRIMARY | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| ST3M571-6H23 | Saturn Fasteners Inc (USA) |
| ST3M571-6H23 | Houston Precision Fasteners I Lp (USA) |
| MB84-6H23 PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| S11-1059-6H23 PRIMARY | Sonic Industries, Inc. Dba Sonic Industries Inc Div Sonic Industries (USA) |
| SLB253-6H23 | Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok (USA) |
| 74328-6H23 PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| VAL23033-6H23 PRIMARY | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| ST3M571-6H23 | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| ST3M571-6H23 | Reid Products Inc. Dba Reid Products Inc (USA) |
| Reference | Meaning |
|---|---|
| 74328-6H23 | 5/2 Secondary reference U.S. Government activity |
| VS3060-6H23 | 5/9 Secondary reference U.S. Government activity |
| ST3M571-6H23 | 7/2 Vendor item drawing reference The Boeing Company Div Defense |
| 74328-6H23 | 5/9 Secondary reference Sps Technologies Inc |
| S371-6H23 | C/1 Advisory reference — outside the item-of-supply concept Huck International, Inc |
| BM3326-6H23 | 5/9 Secondary reference U.S. Government activity |
| S371-6H23 | 5/9 Secondary reference U.S. Government activity |
NSN 5306-00-326-4625 is a Bolt,close Tolerance, manufactured by Hi-Shear Corporation, classified under FSC 5306, Bolts. Status: active.
NSN 5306-00-326-4625 has 16 manufacturer part numbers on file: ST3M571-6H23 (Heartland Precision Fasteners Inc), MB84-6H23 (Hi-Shear Corporation), BM3326-6H23 (Huck International, Inc), VS3060-6H23 (Howmet Global Fastening Systems Inc), GS1030-6H23 (B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace) and 11 more.
Key specifications for MB84-6H23: Extended Washer Thickness: 0.081 INCHES MINIMUM AND 0.101 INCHES MAXIMUM IN; Head Height: 0.378 INCHES MINIMUM AND 0.398 INCHES MAXIMUM IN; Fastener Length: 2.037 INCHES MINIMUM AND 2.067 INCHES MAXIMUM IN; Extended Washer Diameter: 0.639 INCHES MINIMUM AND 0.649 INCHES MAXIMUM IN. 20 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.