| COUNTERSINK ANGLE | 85.0 DEGREES MINIMUM AND 95.0 DEGREES MAXIMUM NUT |
| HARDNESS RATING | 31.0 ROCKWELL C MINIMUM AND 39.0 ROCKWELL C MAXIMUM |
| OVERALL HEIGHT | 0.240 INCHES MINIMUM AND 0.260 INCHES MAXIMUM |
| MATERIAL DOCUMENT AND CLASSIFICATION | AMS 5643 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL COMP 630 OVERALL |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| NUT STYLE | HEXAGON |
| SPECIAL FEATURES | 2 HOLES 0.046 IN. DIA THRU WRENCHING FLAT CORNERS,180 DEG APART |
| WASHER OUTSIDE DIAMETER | 0.740 INCHES MINIMUM AND 0.760 INCHES MAXIMUM |
| WASHER THICKNESS | 0.060 INCHES MINIMUM AND 0.070 INCHES MAXIMUM |
| WIDTH ACROSS FLATS | 0.428 INCHES MINIMUM AND 0.440 INCHES MAXIMUM |
| THREAD CLASS | 3B |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD QUANTITY PER INCH | 28 |
| THREAD SERIES | UNIFIED NATIONAL JOINT FINE (UNJF) |