Matl steel corrosion resistant mil-s-853 - ships - class 6 type e, @drill 2 holes 0.128 in. Diameter in one end spaced 0.188 in. Centrally located, other end drill and ream through two 0.093 in. Diameter holes, arc shaped w/9.855 in. Radius to od, 0.218 in. Thk, 0.250 in. W