| FASTENER LENGTH | 0.250 INCHES NOMINAL |
| HARDNESS RATING | 38.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD DIAMETER | 0.262 INCHES MINIMUM AND 0.270 INCHES MAXIMUM |
| HEAD HEIGHT | 0.159 INCHES MINIMUM AND 0.164 INCHES MAXIMUM |
| HEAD STYLE | FLAT CHAMFER |
| INTERNAL DRIVE STYLE | HEXAGON |
| MATERIAL | STEEL OVERALL |
| MINIMUM YIELD STRENGTH | 155000 POUNDS PER SQUARE INCH |
| MINIMUM TENSILE STRENGTH | 180000 POUNDS PER SQUARE INCH |
| NOMINAL THREAD DIAMETER | 0.1640 INCHES |
| PART NAME ASSIGNED BY CONTROLLING AGENCY | SCREW, CAP SOCKET HEAD |
| SPECIFICATION/STANDARD DATA | 80205-NAS1351 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| SURFACE TREATMENT | CADMIUM AND CHROMATE OVERALL |
| THREAD LENGTH | 0.250 INCHES MINIMUM |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD SERIES DESIGNATOR | UNRF |
| THREAD QUANTITY PER INCH | 36 |
| WIDTH ACROSS FLATS | 0.141 INCHES MINIMUM AND 0.143 INCHES MAXIMUM |