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