| FASTENER LENGTH | 0.620 INCHES MINIMUM AND 0.630 INCHES MAXIMUM |
| HARDNESS RATING | 38.0 ROCKWELL C MINIMUM AND 41.0 ROCKWELL C MAXIMUM OVERALL |
| HEAD STYLE | HEADLESS (SETSCREW) |
| INTERNAL DRIVE STYLE | SLOT |
| LOCKING FEATURE | STRIP THREADS |
| MATERIAL DOCUMENT AND CLASSIFICATION | QQ-B-624 FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| MATERIAL | STEEL COMP 4130 OVERALL |
| NOMINAL THREAD DIAMETER | 0.250 INCHES |
| POINT STYLE | FLAT |
| SPECIAL FEATURES | THD INTERRUPTED BY MACHINED FLATS BEGINNING 0.200 IN. FROM DRIVE END AND ENDING 0.425 FROM DRIVE END,FLATS ARE 0.164 IN. THK |
| SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | QQ-P-416,TYPE 2,CLASS 3 FED SPEC ALL TREATMENT RESPONSES OVERALL |
| SURFACE TREATMENT | CADMIUM AND CHROMATE OVERALL |
| THREAD CLASS | 2A |
| THREAD DIRECTION | RIGHT-HAND |
| THREAD LENGTH | 0.620 INCHES MINIMUM AND 0.630 INCHES MAXIMUM |
| THREAD SERIES DESIGNATOR | UNF |
| THREAD QUANTITY PER INCH | 28 |