| FASTENER LENGTH | 0.660 INCHES MINIMUM AND 0.690 INCHES MAXIMUM |
| HEAD HEIGHT | 0.125 INCHES MINIMUM AND 0.140 INCHES MAXIMUM |
| HEAD STYLE | HEXAGON |
| MATERIAL DOCUMENT AND CLASSIFICATION | NAS621 ASSN STD SINGLE MATERIAL RESPONSE FASTENER |
| MATERIAL DOCUMENT AND CLASSIFICATION | QQ-A-250/5,T3 OR T4 FED SPEC SINGLE MATERIAL RESPONSE PRIMARY WASHER |
| MATERIAL | ALUMINUM ALLOY 2024 PRIMARY WASHER |
| MATERIAL | TITANIUM ALLOY FASTENER |
| MINIMUM TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| PRIMARY WASHER MATERIAL THICKNESS | 0.028 INCHES MINIMUM AND 0.036 INCHES MAXIMUM |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.495 INCHES MINIMUM AND 0.520 INCHES MAXIMUM |
| PRIMARY WASHER STYLE | FLAT |
| WASHER QUANTITY | 1 |
| WIDTH BETWEEN FLATS | 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | MIL-C-5541 MIL SPEC 2ND TREATMENT RESPONSE PRIMARY WASHER |
| SURFACE TREATMENT | ANODIZE OR CHROMATE PRIMARY WASHER |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD CLASS | 3A |
| THREAD LENGTH | 0.400 INCHES MINIMUM AND 0.450 INCHES MAXIMUM |
| THREAD SERIES DESIGNATOR | UNJF |
| THREAD QUANTITY PER INCH | 28 |