Raluminum alloy; 52.80 in. Diameter with hole in middle 16.20 in. Dia; rises parabolically to 4.68 in. High at outer edge of ring that forms the circumference of the centered hole; 12 holes 0.250 to 0.255 in. Diameter drilled and countersunk around outer perimeter spaced equally 30 degs apart; 12 holes 0.250 in. Diameter equally spaced 30 degs apart around ring that forms edge of opening in center; thickness of aluminum 0.040 in.; paint with primer, topcoat and camouflage black