The Bolt,close Tolerance, cataloged under National Stock Number 5306-01-138-9551, 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 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-01-138-9551 |
| Primary Part Number | LB36C4-31 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Hi-Shear Corporation |
| Status | ACTIVE |
| Surface Finish | 63.0 MICROINCHES GRIP |
| Surface Finish | 63.0 MICROINCHES BEARING SURFACE OF HEAD |
| Head Height | 0.126 INCHES MINIMUM AND 0.141 INCHES MAXIMUM IN |
| Fastener Length | 2.427 INCHES MINIMUM AND 2.447 INCHES MAXIMUM IN |
| Thread Length | 0.344 INCHES MINIMUM AND 0.395 INCHES MAXIMUM IN |
| Shank Unthreaded Hole Diameter | 0.076 INCHES MINIMUM AND 0.086 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | AMS 5629 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.937 INCHES MINIMUM AND 1.953 INCHES MAXIMUM IN |
| Width Between Flats | 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN |
| Grip Diameter | 0.2487 INCHES MINIMUM AND 0.2492 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP XM-13 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 2.328 INCHES NOMINAL FIRST HOLE 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 |
|---|---|
| LB36-4-31 | Hi-Shear Corporation (USA) |
| LB36C4-31 PRIMARY | Hi-Shear Corporation (USA) |
| ST3M764C4-31 | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| AS300-4-31 | 5/2 Secondary reference U.S. Government activity |
| 10115972 | 6/9 Informative reference only Nimikkeistokeskus Ncb Finland |
NSN 5306-01-138-9551 is a Bolt,close Tolerance, manufactured by Hi-Shear Corporation, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-138-9551 has 3 manufacturer part numbers on file: LB36-4-31 (Hi-Shear Corporation), LB36C4-31 (Hi-Shear Corporation), ST3M764C4-31 (The Boeing Company Div Defense).
Key specifications for LB36C4-31: Surface Finish: 63.0 MICROINCHES GRIP; Surface Finish: 63.0 MICROINCHES BEARING SURFACE OF HEAD; Head Height: 0.126 INCHES MINIMUM AND 0.141 INCHES MAXIMUM IN; Fastener Length: 2.427 INCHES MINIMUM AND 2.447 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.