| COUNTERBORE DIAMETER | 0.253 INCHES MINIMUM AND 0.263 INCHES MAXIMUM NUT |
| COUNTERSINK ANGLE | 120.0 DEGREES NOMINAL NUT |
| FEATURES PROVIDED | CASEHARDENED |
| LOCKING FEATURE | PREVAILING TORQUE ALL METAL DESIGN |
| MATERIAL DOCUMENT AND CLASSIFICATION | 66 FED STD ALL MATERIAL RESPONSES OVERALL |
| MATERIAL | STEEL COMP 1211 OR STEEL COMP 1212 OR STEEL COMP 1213 OVERALL |
| NOMINAL THREAD SIZE | 0.250 INCHES |
| NUT COUNTERBORE DEPTH | 0.016 INCHES MINIMUM AND 0.020 INCHES MAXIMUM NUT |
| NUT DIAMETER | 0.464 INCHES MINIMUM AND 0.468 INCHES MAXIMUM |
| NUT HEIGHT | 0.196 INCHES MINIMUM AND 0.206 INCHES MAXIMUM |
| NUT STYLE | SPLINE |
| PILOT DIAMETER | 0.396 INCHES NOMINAL |
| PILOT LENGTH | 0.046 INCHES MINIMUM AND 0.054 INCHES MAXIMUM |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TY 2,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| SURFACE TREATMENT | CADMIUM OVERALL |
| THREAD CLASS | 2B |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD SERIES | UNC |
| THREAD QUANTITY PER INCH | 20 |