| THREAD SERIES DESIGNATOR | UNF |
| NOMINAL THREAD DIAMETER | 0.438 INCHES |
| THREAD QUANTITY PER INCH | 20 |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 1.250 INCHES MINIMUM |
| MATERIAL | STEEL COMP 1340H OR |
| STEEL COMP 5140H OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | QQ-S-624 FED SPEC ALL MATERIAL RESPONSES OVERALL |
| HARDNESS RATING | 32.0 ROCKWELL C MINIMUM AND |
| 37.0 ROCKWELL C MAXIMUM OVERALL |
| MINIMUM YIELD STRENGTH | 140000 POUNDS PER SQUARE INCH |
| STYLE DESIGNATOR | ROUND BEND |
| DISTANCE FROM INSIDE CENTER OF BEND TO BOLT END | 6.781 INCHES NOMINAL |
| INSIDE DISTANCE BETWEEN SHANKS | 2.562 INCHES NOMINAL |
| SPECIAL FEATURES | CROWN OF BOLT FLATTENED FOR LARGER SEATING SURFACE |