| THREAD SERIES DESIGNATOR | UNF |
| NOMINAL THREAD DIAMETER | 0.138 INCHES |
| THREAD QUANTITY PER INCH | 40 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.281 INCHES MINIMUM |
| FASTENER LENGTH | 1.031 INCHES NOMINAL |
| MATERIAL | STEEL COMP 4037 OR |
| STEEL COMP 4130 OR |
| STEEL COMP 8630 OR |
| STEEL COMP 8735 OR |
| STEEL COMP 8740 OR |
| STEEL COMP 4140 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | MIL-B-6812 MIL SPEC ALL MATERIAL RESPONSES OVERALL |
| SURFACE TREATMENT | CADMIUM AND |
| CHROMATE OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416 TY 2 CL 3 FED SPEC 5TH TREATMENT RESPONSE 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 | 1060 POUNDS PER SQUARE INCH |
| HEAD STYLE | BUTTON |
| HEAD DIAMETER | 0.312 INCHES NOMINAL |
| HEAD HEIGHT | 0.078 INCHES NOMINAL |
| INTERNAL DRIVE STYLE | SLOT |
| GROOVE DIAMETER | 0.100 INCHES NOMINAL |
| DEPARTURE FROM CITED DOCUMENT | THREAD T PER MIL-S-7742 EXCEPT MAJOR DIA IS NOT TO EXCEED MAX ALLOW BOLT SHANK DIA |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 88044 |
| DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | AN21-16A |