| THREAD SERIES DESIGNATOR | UNC |
| NOMINAL THREAD DIAMETER | 0.3125 INCHES |
| THREAD QUANTITY PER INCH | 18 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.480 INCHES MINIMUM AND |
| 0.500 INCHES MAXIMUM |
| FASTENER LENGTH | 1.105 INCHES MINIMUM AND |
| 1.125 INCHES MAXIMUM |
| MATERIAL | STEEL OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | NASM 21472 NATIONAL STD/SPEC SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT | ZINC OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | ASTM B633, TYPE II, CLASS FE/ZN 5 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| HEAD STYLE | FLAT CHAMFER |
| HEAD DIAMETER | 0.543 INCHES MINIMUM AND |
| 0.562 INCHES MAXIMUM |
| HEAD HEIGHT | 0.209 INCHES NOMINAL |
| CHAMFER ANGLE | 30.0 DEGREES MINIMUM AND |
| 45.0 DEGREES MAXIMUM |
| INTERNAL DRIVE STYLE | HEXAGON |
| WIDTH ACROSS FLATS | 0.188 INCHES NOMINAL |
| SHOULDER SHAPE | ROUND ALL SHOULDERS |
| SHOULDER DIAMETER | 0.371 INCHES MINIMUM AND |
| 0.373 INCHES MAXIMUM ALL SHOULDERS |
| SHOULDER LENGTH | 0.625 INCHES NOMINAL ALL SHOULDERS |
| SPECIFICATION/STANDARD DATA | 80205-NASM51975 NATIONAL STD/SPEC |