| DISTANCE FROM LARGEST DIAMETER OF BEARING SURFACE OF HEAD TO RIBS | 0.228 INCHES NOMINAL |
| FASTENER LENGTH | 3.374 INCHES NOMINAL |
| HARDNESS RATING | 39.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD DIAMETER | 0.640 INCHES NOMINAL |
| HEAD HEIGHT | 0.187 INCHES MINIMUM AND 0.203 INCHES MAXIMUM |
| MATERIAL | STEEL COMP 410 OVERALL |
| MINIMUM TENSILE STRENGTH | 180000 POUNDS PER SQUARE INCH |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| RIB INCLUDED ANGLE | 45.0 DEGREES NOMINAL |
| RIB LENGTH | 1.334 INCHES NOMINAL |
| RIB MAJOR DIAMETER | 0.3720 INCHES MINIMUM AND 0.3740 INCHES MAXIMUM |
| RIB MINOR DIAMETER | 0.3457 INCHES NOMINAL |
| RIB QUANTITY | 36 |
| SHOULDER DIAMETER | 0.3720 INCHES MINIMUM AND 0.3740 INCHES MAXIMUM FIRST SHOULDER |
| SHOULDER LENGTH | 1.334 INCHES NOMINAL FIRST SHOULDER |
| SHOULDER SHAPE | RIBBED FIRST SHOULDER |
| SPECIAL FEATURES | INDEX MARK ON HEAD INDICATES LOCATION OF 3 SHOULDER RIBS REMOVED |
| WIDTH BETWEEN FLATS | 0.553 INCHES MINIMUM AND 0.564 INCHES MAXIMUM |
| SURFACE TREATMENT | PASSIVATE OVERALL |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.396 INCHES MINIMUM |
| THREAD SERIES DESIGNATOR | UNF |
| THREAD QUANTITY PER INCH | 28 |