THREAD SERIES DESIGNATOR | UNF |
NOMINAL THREAD DIAMETER | 0.250 INCHES |
THREAD QUANTITY PER INCH | 28 |
THREAD CLASS | 2A |
THREAD DIRECTION | RIGHT-HAND |
THREAD LENGTH | 0.804 INCHES NOMINAL |
FASTENER LENGTH | 0.875 INCHES NOMINAL |
MATERIAL | STEEL OVERALL |
MATERIAL DOCUMENT AND CLASSIFICATION | SAE J429 GRADE 2 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
SURFACE TREATMENT | CADMIUM OR |
| ZINC OVERALL |
SURFACE TREATMENT DOCUMENT AND CLASSIFICATION | AMS 2400-1 ASSN STD 1ST TREATMENT RESPONSE OR |
| AMS 2402-1 ASSN STD 2ND TREATMENT RESPONSE OVERALL |
HARDNESS RATING | 80.0 ROCKWELL B MINIMUM AND |
| 100.0 ROCKWELL B MAXIMUM OVERALL |
MINIMUM TENSILE STRENGTH | 74000 POUNDS PER SQUARE INCH |
MINIMUM YIELD STRENGTH | 57000 POUNDS PER SQUARE INCH |
HEAD STYLE | HEXAGON |
HEAD HEIGHT | 0.172 INCHES MINIMUM AND |
| 0.190 INCHES MAXIMUM |
WIDTH BETWEEN FLATS | 0.367 INCHES MINIMUM AND |
| 0.375 INCHES MAXIMUM |
INTERNAL DRIVE STYLE | SLOT |
WASHER QUANTITY | 1 |
PRIMARY WASHER STYLE | FLAT EXTERNAL TEETH |
PRIMARY WASHER OUTSIDE DIAMETER | 0.494 INCHES MINIMUM AND |
| 0.510 INCHES MAXIMUM |
PRIMARY WASHER MATERIAL THICKNESS | 0.023 INCHES MINIMUM AND |
| 0.028 INCHES MAXIMUM |