| THREAD SERIES DESIGNATOR | UNC |
| NOMINAL THREAD DIAMETER | 0.375 INCHES |
| THREAD QUANTITY PER INCH | 16 |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.594 INCHES MINIMUM AND |
| 0.719 INCHES MAXIMUM |
| FASTENER LENGTH | 0.719 INCHES MINIMUM AND |
| 0.750 INCHES MAXIMUM |
| MATERIAL | STEEL COMP 1010 OR |
| STEEL COMP 1020 OR |
| STEEL COMP 1050 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | SAE ASSN STD ALL MATERIAL RESPONSES OVERALL |
| SURFACE TREATMENT | CADMIUM OR |
| ZINC OVERALL |
| 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 |
| HEAD STYLE | HEXAGON |
| HEAD HEIGHT | 0.270 INCHES MINIMUM AND |
| 0.295 INCHES MAXIMUM |
| WIDTH BETWEEN FLATS | 0.552 INCHES MINIMUM AND |
| 0.562 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | SLOT |
| WASHER QUANTITY | 1 |
| PRIMARY WASHER STYLE | FLAT EXTERNAL TEETH |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.640 INCHES MINIMUM AND |
| 0.660 INCHES MAXIMUM |
| PRIMARY WASHER MATERIAL THICKNESS | 0.032 INCHES MINIMUM AND |
| 0.040 INCHES MAXIMUM |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 21450 |
| DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | 423569 |