The Bolt,close Tolerance, cataloged under National Stock Number 5306-00-178-8901, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. Government technical data includes 16 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-178-8901 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Status | ACTIVE |
| Head Height | 0.328 INCHES MINIMUM AND 0.360 INCHES MAXIMUM IN |
| Fastener Length | 3.063 INCHES NOMINAL IN |
| Thread Length | 0.389 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN |
| Shank Unthreaded Hole Diameter | 0.141 INCHES MINIMUM AND 0.151 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | MIL-S-18732 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.625 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 2.563 INCHES NOMINAL IN |
| Width Between Flats | 0.928 INCHES MINIMUM AND 0.940 INCHES MAXIMUM IN |
| Grip Diameter | 0.6230 INCHES MINIMUM AND 0.6240 INCHES MAXIMUM IN |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 18 |
| Material | STEEL COMP 431 OVERALL |
| Thread Series Designator | UNF |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 2.871 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 |
| Reference | Meaning |
|---|---|
| 540SE202-265 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5306-00-178-8901 is a Bolt,close Tolerance, classified under FSC 5306, Bolts. Status: active.
Key specifications for 5306-00-178-8901: Head Height: 0.328 INCHES MINIMUM AND 0.360 INCHES MAXIMUM IN; Fastener Length: 3.063 INCHES NOMINAL IN; Thread Length: 0.389 INCHES MINIMUM AND 0.500 INCHES MAXIMUM IN; Shank Unthreaded Hole Diameter: 0.141 INCHES MINIMUM AND 0.151 INCHES MAXIMUM FIRST HOLE 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.