| THREAD SERIES DESIGNATOR | UNC |
| NOMINAL THREAD DIAMETER | 0.138 INCHES |
| THREAD QUANTITY PER INCH | 32 |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.688 INCHES NOMINAL |
| FASTENER LENGTH | 0.719 INCHES MINIMUM AND |
| 0.750 INCHES MAXIMUM |
| MATERIAL | STEEL COMP 1010 OR |
| STEEL COMP 1011 OR |
| STEEL COMP 1013 OR |
| STEEL COMP 1015 OR |
| STEEL COMP 1016 OR |
| STEEL COMP 1017 OR |
| STEEL COMP 1018 OR |
| STEEL COMP 1019 OR |
| STEEL COMP 1020 FASTENER |
| MATERIAL DOCUMENT AND CLASSIFICATION | 66 FED STD SINGLE MATERIAL RESPONSE PRIMARY WASHER |
| 66 FED STD ALL MATERIAL RESPONSES FASTENER |
| SURFACE TREATMENT | CADMIUM OR |
| ZINC OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TYPE 2,CLASS 3 FED SPEC 1ST TREATMENT RESPONSE OR |
| QQ-Z-325,TYPE 1,CLASS3 FED SPEC 2ND TREATMENT RESPONSE OVERALL |
| HEAD STYLE | FILLISTER |
| HEAD DIAMETER | 0.250 INCHES MINIMUM AND |
| 0.270 INCHES MAXIMUM |
| HEAD HEIGHT | 0.102 INCHES MINIMUM AND |
| 0.113 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | SLOT |
| WASHER QUANTITY | 1 |
| PRIMARY WASHER STYLE | SPLIT HELICAL RING |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.243 INCHES MINIMUM AND |
| 0.257 INCHES MAXIMUM |
| PRIMARY WASHER MATERIAL THICKNESS | 0.031 INCHES NOMINAL |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 21450 |
| DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | 593565 |