3/8-16X1 1/4 GR2 HEX CAP SCR HDG F/T SAE J429 GRADE 2 HEX CAP SCREWS HDG FULL THREAD ASME B18.2.1 1996 IFI-7 AF 0.551-0.562” HH 0.226-0.243” AC 0.628-0.650”