| FASTENER LENGTH | 1.250 INCHES NOMINAL |
| FEATURES PROVIDED | FINISHED HEAD |
| GRIP LENGTH | 0.031 INCHES MINIMUM AND 0.062 INCHES MAXIMUM |
| HEAD HEIGHT | 0.131 INCHES MINIMUM AND 0.151 INCHES MAXIMUM |
| HEAD STYLE | CROWNED HEXAGON |
| HOLE DIAMETER | 0.046 INCHES NOMINAL |
| HOLE QUANTITY | 1 |
| HOLE TYPE | DRILLED |
| MATERIAL | STEEL COMP 4140 OR STEEL COMP 8740 OR STEEL COMP 8630 OR STEEL COMP 8735 OR STEEL COMP 4130 OR STEEL COMP 4037 OVERALL |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| SPECIFICATION/STANDARD DATA | 80205-NAS428 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| WIDTH BETWEEN FLATS | 0.428 INCHES MINIMUM AND 0.440 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416;TYPE 2;CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | CADMIUM AND CHROMATE OVERALL |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 1.250 INCHES NOMINAL |
| THREAD QUANTITY PER INCH | 28 |
| THREAD SERIES DESIGNATOR | UNIFIED NATIONAL JOINT FINE (UNJF) |