| COUNTERSINK ANGLE | 120.0 DEGREES NOMINAL NUT |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| LUBRICATION | DRY FILM LUBRICANT |
| OVERALL HEIGHT | 0.313 INCHES MINIMUM AND 0.328 INCHES MAXIMUM |
| MATERIAL DOCUMENT AND CLASSIFICATION | MS5525 MIL STD 1ST MATERIAL RESPONSE OR AMS 5732 ASSN STD 2ND MATERIAL RESPONSE OR AMS 5735 ASSN STD 2ND MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL OR IRON ALLOY 660 OVERALL |
| NOMINAL THREAD SIZE | 0.438 INCHES |
| NUT STYLE | HEXAGON |
| SPECIFICATION/STANDARD DATA | 80205-NAS1291 GOVERNMENT STANDARD |
| WASHER OUTSIDE DIAMETER | 0.708 INCHES MAXIMUM |
| WASHER THICKNESS | 0.035 INCHES MINIMUM |
| WIDTH ACROSS FLATS | 0.494 INCHES MINIMUM AND 0.504 INCHES MAXIMUM |
| TEMP RATING | 450.0 FAHRENHEIT NOMINAL |
| THREAD CLASS | 3B |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD SERIES | UNIFIED NATIONAL JOINT FINE (UNJF) |
| THREAD QUANTITY PER INCH | 20 |