| COUNTERBORE DIAMETER | 0.284 INCHES MINIMUM AND 0.288 INCHES MAXIMUM WASHER |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| LUBRICATION | DRY FILM LUBRICANT |
| OVERALL HEIGHT | 0.340 INCHES MAXIMUM |
| MATERIAL DOCUMENT AND CLASSIFICATION | AMS5639 ASSN STD 1ST MATERIAL RESPONSE OR AMS5697 ASSN STD 1ST MATERIAL RESPONSE OR AMS5686 ASSN STD 2ND MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL COMP 304 OR STEEL COMP 305 OVERALL |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| NUT COUNTERBORE DEPTH | 0.107 INCHES MINIMUM AND 0.117 INCHES MAXIMUM WASHER |
| NUT STYLE | HEXAGON |
| SPECIAL FEATURES | AXIAL TENSILE STRENGTH 5000 LBS MIN; THREADS PER MIL-S-8879 |
| WASHER OUTSIDE DIAMETER | 0.425 INCHES MAXIMUM |
| WIDTH ACROSS FLATS | 0.305 INCHES MINIMUM AND 0.313 INCHES MAXIMUM |
| SURFACE TREATMENT | PASSIVATE OVERALL |
| THREAD CLASS | 3B |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD SERIES | UNIFIED NATIONAL JOINT FINE (UNJF) |
| THREAD QUANTITY PER INCH | 28 |