| COUNTERSINK ANGLE | 80.0 DEGREES MINIMUM AND 84.0 DEGREES MAXIMUM |
| FASTENER LENGTH | 0.750 INCHES NOMINAL |
| HARDNESS RATING | 36.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD DIAMETER | 0.600 INCHES MINIMUM AND 0.656 INCHES MAXIMUM |
| HEAD STYLE | FLAT COUNTERSUNK |
| INTERNAL DRIVE STYLE | HEXAGON |
| MATERIAL DOCUMENT AND CLASSIFICATION | 66 FED STD SINGLE MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL OVERALL |
| MINIMUM YIELD STRENGTH | 130000 POUNDS PER SQUARE INCH |
| MINIMUM TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |
| NOMINAL THREAD DIAMETER | 0.312 INCHES |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | ASTM B633, TYPE II, CLASS FE/ZN 5 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | ZINC OVERALL |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.750 INCHES MAXIMUM |
| THREAD SERIES DESIGNATOR | UNIFIED NATIONAL COARSE (UNC) |
| THREAD QUANTITY PER INCH | 18 |
| WIDTH ACROSS FLATS | 0.188 INCHES NOMINAL |