| FASTENER LENGTH | 0.408 INCHES MINIMUM AND 0.438 INCHES MAXIMUM |
| HEAD HEIGHT | 0.172 INCHES MINIMUM AND 0.190 INCHES MAXIMUM |
| HEAD STYLE | HEXAGON |
| MATERIAL | STEEL COMP 1018 OR STEEL COMP 1019 OR STEEL COMP 1020 OR STEEL COMP 1022 OVERALL |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.460 INCHES MINIMUM AND 0.475 INCHES MAXIMUM |
| PRIMARY WASHER STYLE | FLAT EXTERNAL TEETH |
| PRIMARY WASHER MATERIAL THICKNESS | 0.172 INCHES MINIMUM AND 0.190 INCHES MAXIMUM |
| WASHER QUANTITY | 1 |
| WIDTH BETWEEN FLATS | 0.428 INCHES MINIMUM AND 0.437 INCHES MAXIMUM |
| THREAD CLASS | 2A |
| THREAD LENGTH | 0.318 INCHES MINIMUM AND 0.348 INCHES MAXIMUM |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD QUANTITY PER INCH | 20 |
| THREAD SERIES DESIGNATOR | UNC |