Material steel, corrosion resistant, qq-s-698, 0.062 in. Sheet, 1010/1020; surface treatment, black oxide, mil-c-13924, cl 1; convex edge, 89 degrees to 91 degradius; concave, 0.630 in. Radius; leftand right edges beveled 18 to 22 degrees toward concave edge to a dp 0.093 in. ; 2 holes 0.104 in. Diameter thru, center to center 60 deg, from concave edge, 0.750 in. Radius