| THREAD SERIES DESIGNATOR | UNC |
| THREAD LENGTH | 1.500 INCHES MINIMUM AND |
| 1.688 INCHES MAXIMUM |
| FASTENER LENGTH | 2.422 INCHES MINIMUM AND |
| 2.562 INCHES MAXIMUM |
| MATERIAL | STEEL OVERALL |
| HEAD STYLE | HEXAGON |
| THREAD DIRECTION | RIGHT-HAND |
| NOMINAL THREAD DIAMETER | 0.625 INCHES |
| THREAD QUANTITY PER INCH | 11 |
| THREAD CLASS | 2A |
| MATERIAL DOCUMENT AND CLASSIFICATION | ASTM A449 ASSN STD SINGLE MATERIAL RESPONSE OR |
| ASTM A354 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| SURFACE TREATMENT | CHROMATE ZINC OVERALL |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | ASTM B633,TYPE 2,CLASS 3 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| HARDNESS RATING | 32.0 ROCKWELL C MINIMUM AND |
| 38.0 ROCKWELL C MAXIMUM OVERALL |
| MINIMUM TENSILE STRENGTH | 150000 POUNDS PER SQUARE INCH |
| HEAD HEIGHT | 0.378 INCHES MINIMUM AND |
| 0.403 INCHES MAXIMUM |
| WIDTH BETWEEN FLATS | 0.922 INCHES MINIMUM AND |
| 0.938 INCHES MAXIMUM |
| LOCKING FEATURE | PATCH THREADS |
| FEATURES PROVIDED | FINISHED HEAD |
| DEPARTURE FROM CITED DOCUMENT | FF-S-85,PARAGRAPH 3.1.6,SELF-LOCKING ELEMENT AND PARAGRAPH 3.4.4 ZINC PLATING |
| SUPPLEMENTARY FEATURES | MEETS ANSI B18.2.1 TABLE 4 SIZE 5/8 EXCEPT SELF-LOCKING ELEMENT MIL-F-18240 |
| SPECIFICATION/STANDARD DATA | 81348-FF-S-85 GOVERNMENT SPECIFICATION |
| NONDEFINITIVE SPEC/STD DATA | 2 TYPE AND |
| 10P STYLE AND |
| 5/8-11UNC SIZE |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 81348 |
| NON-DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | FF-S-85 |