Nitralloy, approx 0.840 in. Lg, 0.436 in. O/a dia, 0.06 in.Min, 0.08 in. Max w slot each side, 0.324 in. Min, 0.326 in. Max deep, one 0.09 in. Min, 0.11 in. Max diameter hole in body, rockwell c 34-38, phosphate finish, 125 microinch finish all over, used on gearbox assemblypart no. 541810-6-1, f-111 acft