| HARDNESS RATING | 49.0 ROCKWELL C MAXIMUM |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| LUBRICATION | SOLUBLE LUBRICANT |
| MATERIAL | STEEL COMP 1035 OVERALL OR STEEL COMP 1042 OVERALL OR STEEL COMP 1050 OVERALL OR STEEL COMP 4027 OVERALL OR STEEL COMP 4037 OVERALL OR STEEL COMP 8630 OVERALL OR STEEL COMP 8740 OVERALL |
| PART NAME ASSIGNED BY CONTROLLING AGENCY | NUT, HEXAGON |
| PROPRIETARY CHARACTERISTICS | PACS |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| NUT STYLE | HEXAGON |
| OVERALL HEIGHT | 0.204 INCHES MINIMUM AND 0.219 INCHES MAXIMUM |
| SPECIAL FEATURES | PER DRAWING 950014 THE PART TO BE MODIFIED IS P/N AN364-428C, WHICH IS SUPERSEDED BY P/N MS21042-4. LOCKNUT IS MODIFIED BY STRIPPING OFF CADMIUM PLATING, THEN PHOSPHATE TREAT PER ORDINANCE SPECIFICATION 57-0-2C. HYDROGEN EMBRITTLEMENT RELIEVE PER MP-30 AND MARK PER MP-43. |
| WASHER OUTSIDE DIAMETER | 0.420 INCHES MAXIMUM |
| WASHER THICKNESS | 0.019 INCHES MINIMUM |
| WIDTH ACROSS FLATS | 0.304 INCHES MINIMUM AND 0.316 INCHES MAXIMUM |
| SURFACE TREATMENT | CADMIUM OVERALL |
| TEMP RATING | 450.0 DEG FAHRENHEIT NOMINAL |
| THREAD CLASS | 3B |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD QUANTITY PER INCH | 28 |
| THREAD SERIES | UNJF |