| THREAD SERIES DESIGNATOR | UNF |
| NOMINAL THREAD DIAMETER | 0.312 INCHES |
| THREAD QUANTITY PER INCH | 24 |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.761 INCHES MINIMUM AND |
| 0.844 INCHES MAXIMUM |
| FASTENER LENGTH | 0.844 INCHES MINIMUM AND |
| 0.875 INCHES MAXIMUM |
| MATERIAL | STEEL COMP 1020 OR |
| STEEL COMP 1050 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | SAE ASSN STD ALL MATERIAL RESPONSES OVERALL |
| SURFACE TREATMENT | CADMIUM OR |
| ZINC OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TY 1,CL 3 FED SPEC 1ST TREATMENT RESPONSE OR |
| QQ-Z-325,TY 1,CL 3 FED SPEC 2ND TREATMENT RESPONSE OVERALL |
| HARDNESS RATING | 40.0 ROCKWELL C MINIMUM AND |
| 50.0 ROCKWELL C MAXIMUM PRIMARY WASHER |
| 30.0 ROCKWELL C MINIMUM AND |
| 40.0 ROCKWELL C MAXIMUM BEARING SURFACE OF HEAD |
| HEAD STYLE | HEXAGON |
| HEAD HEIGHT | 0.208 INCHES MINIMUM AND |
| 0.230 INCHES MAXIMUM |
| WIDTH BETWEEN FLATS | 0.489 INCHES MINIMUM AND |
| 0.500 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | SLOT |
| WASHER QUANTITY | 1 |
| PRIMARY WASHER STYLE | FLAT EXTERNAL TEETH |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.567 INCHES MINIMUM AND |
| 0.590 INCHES MAXIMUM |
| PRIMARY WASHER MATERIAL THICKNESS | 0.028 INCHES MINIMUM AND |
| 0.034 INCHES MAXIMUM |
| SPECIAL FEATURES | W/HEADER POINT |