| FASTENER LENGTH | 0.500 INCHES NOMINAL |
| HEAD DIAMETER | 0.389 INCHES MINIMUM AND 0.414 INCHES MAXIMUM |
| HEAD HEIGHT | 0.155 INCHES MINIMUM AND 0.170 INCHES MAXIMUM |
| HEAD STYLE | FILLISTER |
| INTERNAL DRIVE STYLE | CROSS RECESS TYPE 1 |
| MATERIAL | STEEL COMP 1010 OR STEEL COMP 1011 OR STEEL COMP 1013 OR STEEL COMP 1015 OR STEEL COMP 1016 OR STEEL COMP 1017 OR STEEL COMP 1018 OR STEEL COMP 1019 OR STEEL COMP 1020 FASTENER |
| MATERIAL | STEEL COMP 1050 OR STEEL COMP 1551 OR STEEL COMP 1552 OR STEEL COMP 1053 OR STEEL COMP 1054 OR STEEL COMP 1055 OR STEEL COMP 1059 OR STEEL COMP 1060 OR STEEL COMP 1561 OR STEEL COMP 1566 PRIMARY WASHER |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| PRIMARY WASHER MATERIAL THICKNESS | 0.025 INCHES NOMINAL |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.466 INCHES MINIMUM AND 0.478 INCHES MAXIMUM |
| PRIMARY WASHER STYLE | FLAT INTERNAL TEETH |
| WASHER QUANTITY | 1 |
| SURFACE TREATMENT | CADMIUM OR ZINC OVERALL |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.400 INCHES MINIMUM |
| THREAD SERIES DESIGNATOR | UNC |
| THREAD QUANTITY PER INCH | 20 |