Matl cres, mil-s-7720, comp 303, cond b; o/a lg 0.745 to 0.760 in.; o/a diameter 0.490 to 0.500 in.; major diameter 0.556 to 0.562 in.; external thd 9/16-24 nef; thd class 3a; 2 holes through walls 0.187 to 0.192 in. Dia; holes spaced from hole center to end 0.210 to 0.250 in.