| THREAD SERIES | UNC |
| NOMINAL THREAD SIZE | 0.3125 INCHES |
| THREAD QUANTITY PER INCH | 18 |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| MATERIAL | STEEL OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | SAE J429 NATIONAL STD/SPEC SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | WSD-M21P10-B3 MFR REF SINGLE TREATMENT RESPONSE OVERALL |
| NUT STYLE | HEXAGON |
| WASHER OUTSIDE DIAMETER | 0.680 INCHES NOMINAL |
| OVERALL HEIGHT | 0.370 INCHES NOMINAL |
| WIDTH ACROSS FLATS | 0.500 INCHES NOMINAL |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| SPECIAL FEATURES | LOCKING FEATURE IS DEFORMED THREADS |
| PART NAME ASSIGNED BY CONTROLLING AGENCY | NUT,FLG,LKDT .31-18 G5 SPL |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 75Q65 |
| MFR SOURCE CONTROLLING REFERENCE | 4220722 |