4steel astm a322 grade 4340, 4.490 in. Min, 4.500 in. Max dia, 5.438 in. Lg, tapped hole 1.250-12unf-3b, 2.094 in. Deep, 1.753 in. Min, 1.755 in. Max first counterbore dia, 0.750 in. Deep, 3.863 in. Min, 3.885 in. Max second counterbore dia, 1.375 in. Deep