| THREAD SERIES DESIGNATOR | UNF |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| THREAD QUANTITY PER INCH | 28 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.324 INCHES MINIMUM AND |
| 0.364 INCHES MAXIMUM |
| FASTENER LENGTH | 1.459 INCHES MINIMUM AND |
| 1.479 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 | 3680 POUNDS PER SQUARE INCH |
| HEAD STYLE | BUTTON |
| HEAD DIAMETER | 0.484 INCHES MINIMUM AND |
| 0.516 INCHES MAXIMUM |
| HEAD HEIGHT | 0.109 INCHES MINIMUM AND |
| 0.141 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | SLOT |
| GROOVE DIAMETER | 0.191 INCHES MINIMUM AND |
| 0.201 INCHES MAXIMUM |
| DISTANCE FROM HEAD LARGEST BEARING SURFACE TO SHANK HOLE CENTER | 1.297 INCHES MINIMUM AND |
| 1.328 INCHES MAXIMUM FIRST HOLE |
| SHANK UNTHREADED HOLE DIAMETER | 0.066 INCHES MINIMUM AND |
| 0.076 INCHES MAXIMUM FIRST HOLE |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 88044 |
| DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | AN24-23 |