Aluminum alloy, 0.040 in. Thk, 0.995 in. Dia. One hole 0.125 in. Diameter for shaft, two mounting holes 0.094 in. Dia, numerals 0 through 9 at 36 degrees intervals, indexes at 18 degrees intervals entire face, numerals and indicia painted tritium actived luminous green-yellow, face background lusterless black