| COUNTERSINK ANGLE | 70.0 DEGREES NOMINAL |
| FASTENER LENGTH | 0.335 INCHES MINIMUM AND 0.375 INCHES MAXIMUM |
| HEAD DIAMETER | 0.147 INCHES MINIMUM AND 0.155 INCHES MAXIMUM |
| HEAD STYLE | FLAT COUNTERSUNK |
| INTERNAL DRIVE STYLE | HEXAGON |
| MATERIAL DOCUMENT AND CLASSIFICATION | 66 FED STD ALL MATERIAL RESPONSES OVERALL |
| MATERIAL | STEEL COMP 302 OR STEEL COMP 303 OR STEEL COMP 304 OR STEEL COMP 305 OR STEEL COMP 316 OVERALL |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| WIDTH ACROSS FLATS | 0.188 INCHES MINIMUM AND 0.190 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | 171,FINISH 5.4.1 MIL STD SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE FINISH | 32.0 MICROINCHES BEARING SURFACE OF HEAD |
| SURFACE TREATMENT | PASSIVATE OVERALL |
| THREAD LENGTH | 0.227 INCHES MINIMUM AND 0.272 INCHES MAXIMUM |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD QUANTITY PER INCH | 20 |
| THREAD SERIES DESIGNATOR | UNIFIED NATIONAL COARSE (UNC) |