| THREAD DIRECTION | RIGHT-HAND |
| MATERIAL | STEEL CORROSION RESISTING OVERALL |
| NUT STYLE | HEXAGON |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| BEARING SURFACE TYPE | CHAMFERED |
| THREAD SERIES | UNC |
| NOMINAL THREAD SIZE | 0.312 INCHES |
| THREAD QUANTITY PER INCH | 18 |
| THREAD CLASS | 3B |
| MATERIAL DOCUMENT AND CLASSIFICATION | SAE J995. GR 8 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT | ZINC OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | ASTM B633 TY II. FE/ZN 8 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| NUT HEIGHT | 0.258 INCHES MINIMUM AND |
| 0.336 INCHES MAXIMUM |
| WIDTH ACROSS FLATS | 0.489 INCHES MINIMUM AND |
| 0.502 INCHES MAXIMUM |
| TEMP RATING | 250.0 DEG FAHRENHEIT NOMINAL |
| BEARING SURFACE FINISH | 125.0 MICROINCHES |
| SUPPLEMENTARY FEATURES | HARDNESS NOT RATED |
| SPECIFICATION/STANDARD DATA | 81349-MIL-DTL-45913/4 GOVERNMENT SPECIFICATION |
| PART NAME ASSIGNED BY CONTROLLING AGENCY | NUT, SELF-LOCKING, HEXAGON ALL-METAL LOCKING FEATURE, 250 DEGREE, UNC-3B |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 81349 |
| DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | M45913/4-5CG8Z |