1/2 -20X2 3/4 GR8 HEX CAP SCR Y/Z SAE J429 GRADE 8 UNF HEX CAP SCREWS YELLOW ZINC ASME B18.2.1 1996 IFI-7 AF 0.736-0.750” HH 0.302-0.323” AC 0.840-0.866”