The Bolt,internal Wrenching, cataloged under National Stock Number 5306-01-066-8644, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. Government technical data includes 21 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5306-01-066-8644 |
| Item Name | Bolt,internal Wrenching |
| FSC / FSG | 5306 / 53 — Bolts |
| Status | ACTIVE |
| Width Across Flats | 0.219 INCHES MINIMUM AND 0.221 INCHES MAXIMUM IN |
| Head Height | 0.312 INCHES NOMINAL IN |
| Fastener Length | 2.173 INCHES MINIMUM AND 2.203 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TYPE 2,CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.537 INCHES MINIMUM AND 0.587 INCHES MAXIMUM IN |
| Hardness Rating | 34.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM OVERALL |
| Hole Configuration Style | ROUND INTERNAL HEXAGON |
| Material Document and Classification | MIL-S-5000 MIL STD 1ST MATERIAL RESPONSE OR MIL-S-5026 MIL STD 2ND MATERIAL RESPONSE OR MIL-S-6049 MIL STD 3RD MATERIAL RESPONSE OR MIL-S-6098 MIL STD 4TH MATERIAL RESPONSE OR MIL-S-8503 MIL STD 5TH MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Thread Direction | RIGHT-HAND |
| Surface Treatment | CADMIUM OVERALL |
| Minimum Tensile Strength | 160000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL OVERALL |
| Hole Quantity | 4 |
| Thread Series Designator | UNF |
| Hole Type | DRILLED |
| Hole Diameter | 0.055 INCHES NOMINAL IN |
| Head Diameter | 0.521 INCHES MINIMUM AND 0.531 INCHES MAXIMUM 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 |
|---|---|
| MS20005H26 | 2/2 Government specification standardization U.S. Government activity |
NSN 5306-01-066-8644 is a Bolt,internal Wrenching, classified under FSC 5306, Bolts. Status: active.
Key specifications for 5306-01-066-8644: Width Across Flats: 0.219 INCHES MINIMUM AND 0.221 INCHES MAXIMUM IN; Head Height: 0.312 INCHES NOMINAL IN; Fastener Length: 2.173 INCHES MINIMUM AND 2.203 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TYPE 2,CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL. 21 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.