| DEPARTURE FROM CITED DESIGNATOR | AS M0DIFIED BY SURFACE TREATMENT |
| FASTENER LENGTH | 0.375 INCHES NOMINAL |
| HARDNESS RATING | 45.0 ROCKWELL C MINIMUM AND 53.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD STYLE | HEADLESS (SETSCREW) |
| INTERNAL DRIVE STYLE | HEXAGON |
| MATERIAL DOCUMENT AND CLASSIFICATION | 66 FED STD SINGLE MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL COMP 4037 OVERALL |
| NOMINAL THREAD DIAMETER | 0.312 INCHES |
| NONDEFINITIVE SPEC/STD DATA | 1 TYPE AND 4 STYLE |
| POINT STYLE | CUP |
| WIDTH ACROSS FLATS | 0.156 INCHES MINIMUM AND 0.158 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TY 2,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | CADMIUM OVERALL |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.375 INCHES MINIMUM |
| THREAD QUANTITY PER INCH | 18 |
| THREAD SERIES DESIGNATOR | UNIFIED NATIONAL COARSE (UNC) |