| COUNTERSINK ANGLE | 80.0 DEGREES MINIMUM AND 84.0 DEGREES MAXIMUM |
| FASTENER LENGTH | 0.422 INCHES MINIMUM AND 0.453 INCHES MAXIMUM |
| HARDNESS RATING | 36.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD DIAMETER | 0.480 INCHES MINIMUM AND 0.531 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 TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |
| MINIMUM YIELD STRENGTH | 130000 POUNDS PER SQUARE INCH |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| NONDEFINITIVE SPEC/STD DATA | 4 TYPE |
| WIDTH ACROSS FLATS | 0.156 INCHES NOMINAL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TY 2,CL 3 FED SPEC ALL TREATMENT RESPONSES OVERALL |
| SURFACE TREATMENT | CADMIUM AND CHROMATE OVERALL |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.190 INCHES MINIMUM AND 0.292 INCHES MAXIMUM |
| THREAD QUANTITY PER INCH | 28 |
| THREAD SERIES DESIGNATOR | UNF |