| DIAMETER OF RECESSED PORTION OF SHANK | 0.207 INCHES MINIMUM AND 0.210 INCHES MAXIMUM |
| HARDNESS RATING | 28.0 ROCKWELL C MINIMUM AND 34.0 ROCKWELL C MAXIMUM |
| LENGTH OF RECESSED PORTION OF SHANK | 3.360 INCHES NOMINAL |
| OVERALL LENGTH | 4.760 INCHES NOMINAL |
| MATERIAL DOCUMENT AND CLASSIFICATION | ASTM A322 ASSN STD SINGLE MATERIAL RESPONSE OR ASTM A331 ASSN STD SINGLE MATERIAL RESPONSE |
| MATERIAL | STEEL COMP 8640 |
| NOMINAL THREAD SIZE | 0.250 INCHES NUT THREAD |
| NOMINAL THREAD SIZE | 0.250 INCHES STUD THREAD |
| STYLE DESIGNATOR | RECESSED |
| SURFACE TREATMENT | CADMIUM OR ZINC OVERALL |
| THREAD CLASS | 3A NUT THREAD |
| THREAD DIRECTION | RIGHT-HAND NUT THREAD |
| THREAD DIRECTION | RIGHT-HAND STUD THREAD |
| THREAD LENGTH | 0.500 INCHES NOMINAL NUT THREAD |
| THREAD LENGTH | 0.500 INCHES NOMINAL STUD THREAD |
| THREAD PITCH DIAMETERS | +0.2261 TO 0.2274 INCHES STUD THREAD |
| THREAD QUANTITY PER INCH | 20 STUD THREAD |
| THREAD QUANTITY PER INCH | 28 NUT THREAD |
| THREAD SERIES DESIGNATOR | UNF NUT THREAD |
| THREAD SERIES DESIGNATOR | UNS STUD THREAD |