| EXTENDED WASHER DIAMETER | 0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM |
| EXTENDED WASHER THICKNESS | 0.060 INCHES MINIMUM AND 0.070 INCHES MAXIMUM |
| FASTENER LENGTH | 1.110 INCHES MINIMUM AND 1.130 INCHES MAXIMUM |
| HEAD HEIGHT | 0.293 INCHES MINIMUM AND 0.313 INCHES MAXIMUM |
| HEAD STYLE | DOUBLE HEXAGON EXTENDED WASHER |
| MATERIAL | STEEL OVERALL |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| SHOULDER DIAMETER | 0.2750 INCHES MINIMUM AND 0.2755 INCHES MAXIMUM FIRST SHOULDER |
| SHOULDER SHAPE | ROUND FIRST SHOULDER |
| SHOULDER LENGTH | 0.300 INCHES MINIMUM AND 0.310 INCHES MAXIMUM FIRST SHOULDER |
| SPECIAL FEATURES | WITH UNDERCUT BETWEEN SHOULDER AND THREADS |
| WIDTH BETWEEN FLATS | 0.312 INCHES NOMINAL |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.800 INCHES MINIMUM AND 0.830 INCHES MAXIMUM |
| THREAD QUANTITY PER INCH | 28 |
| THREAD SERIES DESIGNATOR | UNIFIED NATIONAL JOINT FINE (UNJF) |