| FASTENER LENGTH | 1.250 INCHES NOMINAL |
| HARDNESS RATING | 45.0 ROCKWELL C MINIMUM AND 53.0 ROCKWELL C MAXIMUM PRIMARY WASHER |
| HEAD HEIGHT | 0.270 INCHES MINIMUM AND 0.295 INCHES MAXIMUM |
| HEAD STYLE | HEXAGON |
| INTERNAL DRIVE STYLE | CROSS RECESS TYPE 1 |
| 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 |
| NOMINAL THREAD DIAMETER | 0.375 INCHES |
| PRIMARY WASHER MATERIAL THICKNESS | 0.094 INCHES MINIMUM |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.635 INCHES MINIMUM AND 0.651 INCHES MAXIMUM |
| PRIMARY WASHER STYLE | SPLIT HELICAL RING |
| WASHER QUANTITY | 1 |
| WIDTH BETWEEN FLATS | 0.551 INCHES MINIMUM AND 0.562 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TY 1,CL 3 FED SPEC 1ST TREATMENT RESPONSE OR QQ-Z-325,TY 1,CL 3 FED SPEC 2ND TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | CADMIUM OR ZINC OVERALL |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD CLASS | 2A |
| THREAD LENGTH | 1.156 INCHES MAXIMUM |
| THREAD SERIES DESIGNATOR | UNC |
| THREAD QUANTITY PER INCH | 16 |