| THREAD SERIES | UNJF |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| THREAD QUANTITY PER INCH | 28 |
| THREAD CLASS | 3B |
| THREAD DIRECTION | RIGHT-HAND |
| MATERIAL | STEEL COMP 4027 OR |
| STEEL COMP 4037 OR |
| STEEL COMP 8630 OR |
| STEEL COMP 8740 OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | AISI ASSN STD ALL MATERIAL RESPONSES OVERALL |
| SURFACE TREATMENT | ZINC AND |
| CHROMATE OVERALL EXCEPT INSERT |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | ASTMB633 TY2 ASSN STD SINGLE TREATMENT RESPONSE OVERALL EXCEPT INSERT |
| HARDNESS RATING | 49.0 ROCKWELL C MAXIMUM |
| NUT STYLE | HEXAGON |
| WASHER OUTSIDE DIAMETER | 0.420 INCHES MAXIMUM |
| OVERALL HEIGHT | 0.204 INCHES MINIMUM AND |
| 0.219 INCHES MAXIMUM |
| WASHER THICKNESS | 0.019 INCHES MINIMUM |
| WIDTH ACROSS FLATS | 0.304 INCHES MINIMUM AND |
| 0.316 INCHES MAXIMUM |
| LOCKING FEATURE | PREVAILING TORQUE WITH NONMETALLIC INSERT |
| TEMP RATING | 450.0 DEG FAHRENHEIT NOMINAL |
| SPECIAL FEATURES | FINISH COLOR BRONZE OR OLIVE DRAB |