The Bolt,close Tolerance, cataloged under National Stock Number 5306-00-003-4091, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. Government technical data includes 20 specifications, cited from the U.S. Government catalog. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-003-4091 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Status | ACTIVE |
| Surface Finish | 63.0 MICROINCHES GRIP |
| Surface Finish | 63.0 MICROINCHES BEARING SURFACE OF HEAD |
| Head Height | 0.189 INCHES MINIMUM AND 0.189 INCHES MINIMUM AND 0.204 INCHES MAXIMUM0.204 INCHES MAXIMUM IN |
| Fastener Length | 5.226 INCHES MINIMUM AND 5.226 INCHES MINIMUM AND 5.246 INCHES MAXIMUM5.246 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY 2 CL 2 FED SPEC ALL TREATMENT RESPONSES OVERALL |
| Thread Length | 0.356 INCHES MINIMUM AND 0.356 INCHES MINIMUM AND 0.438 INCHES MAXIMUM0.438 INCHES MAXIMUM IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 41.0 ROCKWELL C MAXIMUM OVERALL |
| Shank Unthreaded Hole Diameter | 0.106 INCHES MINIMUM AND 0.116 INCHES MAXIMUM FIRST HOLE IN |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | DISHED HEXAGONDISHED HEXAGON |
| Thread Direction | RIGHT-HANDRIGHT-HAND |
| Grip Length | 3.188 INCHES MINIMUM AND 3.204 INCHES MAXIMUM IN |
| Width Between Flats | 0.553 INCHES MINIMUM AND 0.553 INCHES MINIMUM AND 0.564 INCHES MAXIMUM0.564 INCHES MAXIMUM IN |
| Grip Diameter | 0.3733 INCHES MINIMUM AND 0.3733 INCHES MINIMUM AND 0.3742 INCHES MAXIMUM0.3742 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Thread Class | 3A3A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP E4340 OR STEEL COMP 4140 OR STEEL COMP 8740 OR STEEL COMP 4130 OR STEEL COMP 6150 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 5.111 INCHES MINIMUM AND 5.189 INCHES MAXIMUM 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 |
| Reference | Meaning |
|---|---|
| 106467-6-75 | 5/2 Secondary reference U.S. Government activity |
| CIPRD-MS27576-6-75R | 5/9 Secondary reference Defense Logistics Agency Dba Defense Supply Center Philadelphia |
| MS27576-6-75 | 5/9 Secondary reference U.S. Government activity |
| MS27576-6-75R | 3/2 Design control — primary reference U.S. Government activity |
| MS27576-6-75 | 5/9 Secondary reference U.S. Government activity |
| AS194-6-75 | 5/9 Secondary reference U.S. Government activity |
| CA4510-6-75 | 5/9 Secondary reference Howmet Global Fastening Systems Inc. Div Tridair Products |
NSN 5306-00-003-4091 is a Bolt,close Tolerance, classified under FSC 5306, Bolts. Status: active.
Key specifications for 5306-00-003-4091: Surface Finish: 63.0 MICROINCHES GRIP; Surface Finish: 63.0 MICROINCHES BEARING SURFACE OF HEAD; Head Height: 0.189 INCHES MINIMUM AND 0.189 INCHES MINIMUM AND 0.204 INCHES MAXIMUM0.204 INCHES MAXIMUM IN; Fastener Length: 5.226 INCHES MINIMUM AND 5.226 INCHES MINIMUM AND 5.246 INCHES MAXIMUM5.246 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.