| HARDNESS RATING | 28.0 ROCKWELL C MINIMUM AND 32.0 ROCKWELL C MAXIMUM |
| NOMINAL THREAD SIZE | 0.250 INCHES NUT THREAD |
| NOMINAL THREAD SIZE | 0.312 INCHES STUD THREAD |
| OVERALL LENGTH | 3.281 INCHES NOMINAL |
| MATERIAL DOCUMENT AND CLASSIFICATION | AMS 6280 ASSN STD 1ST MATERIAL RESPONSE OR AMS 6322 ASSN STD 2ND MATERIAL RESPONSE OR AMS 6324 ASSN STD 2ND MATERIAL RESPONSE OR AMS 6370 ASSN STD 3RD MATERIAL RESPONSE |
| MATERIAL | STEEL COMP 8630 OR STEEL COMP 8740 OR STEEL COMP 4130 |
| SHANK DIAMETER | 0.250 INCHES NOMINAL |
| SPECIAL FEATURES | STUD END THREAD 0.002 IN. OVERSIZE |
| STYLE DESIGNATOR | STEPPED |
| SURFACE FINISH | 100.0 MICROINCHES NUT THD |
| SURFACE FINISH | 40.0 MICROINCHES STUD THD |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | AMS 2400 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | CADMIUM OVERALL |
| THREAD CLASS | 3A NUT THREAD |
| THREAD DIRECTION | RIGHT-HAND NUT THREAD |
| THREAD DIRECTION | RIGHT-HAND STUD THREAD |
| THREAD LENGTH | 0.438 INCHES NOMINAL STUD THREAD |
| THREAD LENGTH | 0.500 INCHES MINIMUM NUT THREAD |
| THREAD PITCH DIAMETERS | +0.2805 TO 0.2821 INCHES STUD THREAD |
| THREAD QUANTITY PER INCH | 18 STUD THREAD |
| THREAD QUANTITY PER INCH | 28 NUT THREAD |
| THREAD SERIES DESIGNATOR | UNF NUT THREAD |
| THREAD SERIES DESIGNATOR | UNS STUD THREAD |