| THREAD SERIES DESIGNATOR | UNJF |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| THREAD QUANTITY PER INCH | 28 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.403 INCHES NOMINAL |
| FASTENER LENGTH | 1.263 INCHES MINIMUM AND |
| 1.293 INCHES MAXIMUM |
| MATERIAL | IRON ALLOY 660 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | AMS5731 ASSN STD SINGLE MATERIAL RESPONSE OR |
| AMS5732 ASSN STD SINGLE MATERIAL RESPONSE OR |
| AMS5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT | PASSIVATE OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| MINIMUM TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |
| HEAD STYLE | FLAT COUNTERSUNK |
| HEAD DIAMETER | 0.4640 INCHES MINIMUM AND |
| 0.5066 INCHES MAXIMUM |
| WIDTH BETWEEN FLATS | 0.553 INCHES MINIMUM AND |
| 0.564 INCHES MAXIMUM |
| COUNTERSINK ANGLE | 99.0 DEGREES MINIMUM AND |
| 101.0 DEGREES MAXIMUM |
| INTERNAL DRIVE STYLE | OFFSET CRUCIFORM (TORQUE SET) |
| GRIP LENGTH | 0.865 INCHES MINIMUM AND |
| 0.885 INCHES MAXIMUM |
| GRIP DIAMETER | 0.2485 INCHES MINIMUM AND |
| 0.2495 INCHES MAXIMUM |
| SURFACE FINISH | 32.0 MICROINCHES BEARING SURFACE OF HEAD |
| 32.0 MICROINCHES GRIP |
| 32.0 MICROINCHES THREADS |
| SPECIFICATION/STANDARD DATA | 80205-NAS1580 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |