| THREAD SERIES DESIGNATOR | UNRF |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| THREAD QUANTITY PER INCH | 28 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.524 INCHES MINIMUM AND |
| 0.625 INCHES MAXIMUM |
| FASTENER LENGTH | 0.595 INCHES MINIMUM AND |
| 0.625 INCHES MAXIMUM |
| MATERIAL | IRON ALLOY 660 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | AMS5731 ASSN STD SINGLE MATERIAL RESPONSE OR |
| AMS5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT | SILVER OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | AMS2411 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| HARDNESS RATING | 33.0 ROCKWELL C MINIMUM AND |
| 42.0 ROCKWELL C MAXIMUM OVERALL |
| MINIMUM TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |
| MINIMUM YIELD STRENGTH | 120000 POUNDS PER SQUARE INCH |
| HEAD STYLE | FLAT CHAMFER |
| HEAD DIAMETER | 0.365 INCHES MINIMUM AND |
| 0.375 INCHES MAXIMUM |
| HEAD HEIGHT | 0.244 INCHES MINIMUM AND |
| 0.250 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | HEXAGON |
| WIDTH ACROSS FLATS | 0.188 INCHES MINIMUM AND |
| 0.190 INCHES MAXIMUM |
| HOLE CONFIGURATION STYLE | ROUND INTERNAL HEXAGON |
| HOLE TYPE | DRILLED |
| HOLE QUANTITY | 6 |
| HOLE DIAMETER | 0.044 INCHES MINIMUM AND |
| 0.050 INCHES MAXIMUM |
| SPECIFICATION/STANDARD DATA | 80205-NAS1351 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| PRECIOUS MATERIAL | SILVER |
| PRECIOUS MATERIAL AND LOCATION | OVERALL SILVER |