| THREAD SERIES DESIGNATOR | UNC |
| NOMINAL THREAD DIAMETER | 0.437 INCHES |
| THREAD QUANTITY PER INCH | 14 |
| THREAD CLASS | 3A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 1.375 INCHES MINIMUM |
| FASTENER LENGTH | 2.219 INCHES MINIMUM AND |
| 2.281 INCHES MAXIMUM |
| MATERIAL | PLASTIC POLYAMIDE LOCKING FEATURE |
| STEEL FASTENER |
| SURFACE TREATMENT | CADMIUM AND |
| CHROMATE FASTENER |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TYPE 2 CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE FASTENER |
| HARDNESS RATING | 36.0 ROCKWELL C MINIMUM AND |
| 45.0 ROCKWELL C MAXIMUM OVERALL |
| MINIMUM TENSILE STRENGTH | 160000 POUNDS PER SQUARE INCH |
| MINIMUM YIELD STRENGTH | 130000 POUNDS PER SQUARE INCH |
| HEAD STYLE | FLAT CHAMFER |
| HEAD DIAMETER | 0.642 INCHES MINIMUM AND |
| 0.656 INCHES MAXIMUM |
| HEAD HEIGHT | 0.430 INCHES MINIMUM AND |
| 0.437 INCHES MAXIMUM |
| INTERNAL DRIVE STYLE | HEXAGON |
| WIDTH ACROSS FLATS | 0.375 INCHES MINIMUM AND |
| 0.379 INCHES MAXIMUM |
| LOCKING FEATURE | PATCH OR |
| PELLET OR |
| STRIP THREADS |
| NONDEFINITIVE SPEC/STD DATA | 6 TYPE |
| DEPARTURE FROM CITED DESIGNATOR | AS MODIFIED BY LOCKING FEATURE AND THREAD LENGTH |
| SPEC/STD CONTROLLING DATA | |
| MANUFACTURERS CODE | 81348 |
| NON-DEFINITIVE GOVERNMENT SPEC/STD REFERENCE | FFS86 |