| COUNTERBORE DIAMETER | 0.277 INCHES MINIMUM AND 0.287 INCHES MAXIMUM NUT |
| HARDNESS RATING | 40.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| LUBRICATION | DRY FILM LUBRICANT |
| OVERALL HEIGHT | 0.271 INCHES MINIMUM AND 0.291 INCHES MAXIMUM |
| MATERIAL DOCUMENT AND CLASSIFICATION | MIL-S-6049 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-8695 MIL SPEC 2ND MATERIAL RESPONSE NUT |
| MATERIAL | STEEL COMP 8740 OR STEEL COMP 4037 NUT |
| MATERIAL | STEEL WASHER |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| NUT COUNTERBORE DEPTH | 0.072 INCHES MINIMUM AND 0.087 INCHES MAXIMUM NUT |
| NUT STYLE | FLAT WITH TURNED UP EDGE |
| WASHER OUTSIDE DIAMETER | 0.460 INCHES MAXIMUM |
| WIDTH ACROSS FLATS | 0.274 INCHES MINIMUM AND 0.284 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416 TYPE II CLASS 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | CADMIUM OVERALL |
| TEMP RATING | 450.0 FAHRENHEIT NOMINAL |
| THREAD CLASS | 3B |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD QUANTITY PER INCH | 28 |
| THREAD SERIES | UNIFIED NATIONAL JOINT FINE (UNJF) |