| COUNTERSINK ANGLE | 80.0 DEGREES MINIMUM AND 82.0 DEGREES MAXIMUM |
| FASTENER LENGTH | 0.625 INCHES NOMINAL |
| HEAD DIAMETER | 0.452 INCHES MINIMUM AND 0.507 INCHES MAXIMUM |
| HEAD STYLE | FLAT COUNTERSUNK |
| INTERNAL DRIVE STYLE | CROSS RECESS TYPE 1 |
| MATERIAL | |
| PRIMARY WASHER MATERIAL THICKNESS | 0.019 INCHES MINIMUM AND 0.025 INCHES MAXIMUM |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.275 INCHES MINIMUM AND 0.289 INCHES MAXIMUM |
| PRIMARY WASHER STYLE | COUNTERSINK EXTERNAL TEETH |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| SURFACE TREATMENT | |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.503 INCHES MINIMUM |
| THREAD QUANTITY PER INCH | 20 |
| THREAD SERIES DESIGNATOR | UNIFIED NATIONAL COARSE (UNC) |
| WASHER QUANTITY | 1 |