| THREAD SERIES DESIGNATOR | UNRC |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| THREAD QUANTITY PER INCH | 20 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.448 INCHES MINIMUM AND |
| 0.550 INCHES MAXIMUM |
| FASTENER LENGTH | 0.590 INCHES MINIMUM AND |
| 0.620 INCHES MAXIMUM |
| MATERIAL | STEEL OVERALL |
| MATERIAL DOCUMENT AND CLASSIFICATION | SAE ASSN STD ALL MATERIAL RESPONSES PRIMARY WASHER |
| GM275-M,FSCM 11862 MFR REF SINGLE MATERIAL RESPONSE FASTENER |
| SURFACE TREATMENT | PHOSPHATE ZINC OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | GM6111-M(400),FSCM 11862 MFR REF SINGLE TREATMENT RESPONSE OVERALL |
| HARDNESS RATING | 40.0 ROCKWELL C MINIMUM AND |
| 48.0 ROCKWELL C MAXIMUM PRIMARY WASHER |
| HEAD STYLE | HEXAGON |
| HEAD HEIGHT | 0.172 INCHES MINIMUM AND |
| 0.190 INCHES MAXIMUM |
| WIDTH BETWEEN FLATS | 0.428 INCHES MINIMUM AND |
| 0.438 INCHES MAXIMUM |
| WASHER QUANTITY | 1 |
| PRIMARY WASHER STYLE | SPRING TENSION |
| PRIMARY WASHER OUTSIDE DIAMETER | 0.495 INCHES MINIMUM AND |
| 0.515 INCHES MAXIMUM |
| PRIMARY WASHER MATERIAL THICKNESS | 0.059 INCHES MINIMUM AND |
| 0.071 INCHES MAXIMUM |
| THE MANUFACTURERS DATA | |
| MANUFACTURERS CODE | 7X677 |
| DESIGN CONTROL REFERENCE | 9439771 |