The Bolt,close Tolerance, cataloged under National Stock Number 5306-01-493-5541, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Huck International, Inc. Government technical data includes 16 specifications, cited from the U.S. Government catalog. The record lists 14 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5306-01-493-5541 |
| Primary Part Number | S343L4-6F |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Huck International, Inc |
| Status | ACTIVE |
| Extended Washer Thickness | 0.036 INCHES NOMINAL IN |
| Head Height | 0.250 INCHES NOMINAL IN |
| Fastener Length | 0.843 INCHES NOMINAL IN |
| Extended Washer Diameter | 0.470 INCHES NOMINAL IN |
| Thread Length | 0.468 INCHES NOMINAL IN |
| Supplementary Features | IVD COATING; DRY FILM LUBRICATION |
| Nominal Thread Diameter | 0.062 INCHES IN |
| Head Style | SPLINE EXTENDED WASHER |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.375 INCHES NOMINAL IN |
| Head Minor Diameter | 0.312 INCHES NOMINAL IN |
| Grip Diameter | 0.248 INCHES NOMINAL IN |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| 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 |
|---|---|
| S343L4-6F PRIMARY | Huck International, Inc (USA) |
| MB156L4-6F PRIMARY | Hi-Shear Corporation (USA) |
| VFK600L4-6F PRIMARY | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| GS1032-L4-6F PRIMARY | B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace (USA) |
| PBF1267L4-6F PRIMARY | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| AIC763L4-6F PRIMARY | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| MB156L4-6F PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| SLB255-L4-6F PRIMARY | Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok (USA) |
| ST3M753L4-6F | Houston Precision Fasteners I Lp (USA) |
| VS3190L4-6F PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| HP7753L4-6F PRIMARY | Heartland Precision Fasteners Inc (USA) |
| ST3M753L4-6F PRIMARY | Fastener Innovation Technology, Inc. Dba F I T (USA) |
| ST3M753L4-6F PRIMARY | The Boeing Company Div Defense (USA) |
| 122897L4-6F PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| 122897L4-6F | 5/9 Secondary reference Sps Technologies Inc |
| 122897L4-6F | 3/2 Design control — primary reference U.S. Government activity |
NSN 5306-01-493-5541 is a Bolt,close Tolerance, manufactured by Huck International, Inc, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-493-5541 has 14 manufacturer part numbers on file: S343L4-6F (Huck International, Inc), MB156L4-6F (Hi-Shear Corporation), VFK600L4-6F (Valley-Todeco, Inc. Dba Arconic Fastening Systems), GS1032-L4-6F (B & B Specialties Inc Dba Gs Aerospace Div Gs Aerospace), PBF1267L4-6F (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners) and 9 more.
Key specifications for S343L4-6F: Extended Washer Thickness: 0.036 INCHES NOMINAL IN; Head Height: 0.250 INCHES NOMINAL IN; Fastener Length: 0.843 INCHES NOMINAL IN; Extended Washer Diameter: 0.470 INCHES NOMINAL IN. 16 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.