| MATERIAL | IRON ALLOY 660 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | AMS5737 NATIONAL STD/SPEC SINGLE MATERIAL RESPONSE OR |
| AMS5731 NATIONAL STD/SPEC SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT | PASSIVATE OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | HI-SHEAR SPEC 258 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| MINIMUM TENSILE STRENGTH | 5820 POUNDS PER SQUARE INCH |
| HEAD STYLE | FLUSH COUNTERSUNK |
| HEAD MAJOR DIAMETER | 0.5018 INCHES MINIMUM AND |
| 0.5066 INCHES MAXIMUM |
| COUNTERSINK ANGLE | 99.0 DEGREES MINIMUM AND |
| 101.0 DEGREES MAXIMUM |
| SHANK STYLE | PIN-RIVET, STRAIGHT, THREADED |
| FASTENER LENGTH | 1.1450 INCHES NOMINAL |
| WIDTH BETWEEN FLATS | 0.0947 INCHES MINIMUM AND |
| 0.0967 INCHES MAXIMUM |
| SHANK DIAMETER | 0.2641 INCHES MINIMUM AND |
| 0.2651 INCHES MAXIMUM |
| GRIP LENGTH | 0.750 INCHES NOMINAL |
| THREAD SERIES DESIGNATOR | UNJF |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| THREAD CLASS | 3A |
| THREAD QUANTITY PER INCH | 28 |