| THREAD SERIES DESIGNATOR | UNF |
| NOMINAL THREAD DIAMETER | 0.312 INCHES |
| THREAD QUANTITY PER INCH | 24 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.328 INCHES MINIMUM AND |
| 0.392 INCHES MAXIMUM |
| FASTENER LENGTH | 2.156 INCHES MINIMUM AND |
| 2.188 INCHES MAXIMUM |
| 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 |
| SURFACE TREATMENT | CADMIUM AND |
| CHROMATE OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TY 2 CL 3 FED SPEC ALL TREATMENT RESPONSES OVERALL |
| HARDNESS RATING | 26.0 ROCKWELL C MINIMUM AND |
| 32.0 ROCKWELL C MAXIMUM OVERALL |
| MINIMUM TENSILE STRENGTH | 125000 POUNDS PER SQUARE INCH |
| SINGLE SHEAR STRENGTH | 5750 POUNDS PER SQUARE INCH |
| HEAD STYLE | BUTTON |
| HEAD DIAMETER | 0.609 INCHES MINIMUM AND |
| 0.641 INCHES MAXIMUM |
| HEAD HEIGHT | 0.140 INCHES MINIMUM AND |
| 0.172 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | SLOT |
| GROOVE DIAMETER | 0.245 INCHES MINIMUM AND |
| 0.255 INCHES MAXIMUM |
| DISTANCE FROM HEAD LARGEST BEARING SURFACE TO SHANK HOLE CENTER | 1.984 INCHES MINIMUM AND |
| 2.016 INCHES MAXIMUM FIRST HOLE |
| SHANK UNTHREADED HOLE DIAMETER | 0.076 INCHES MINIMUM AND |
| 0.086 INCHES MAXIMUM FIRST HOLE |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 88044 |
| DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | AN25-34 |