"NYLON,L-P-410,COMP6/6; TRIANGULAR BASE FLANGE INSCRIBED IN 4.250 IN. DIA CIRCLE; CONICAL PORT OPENING 1.000 IN. H W/60.0 DEG FLARE; CONE TERMINATES IN A 1.638 IN. HOLE AT FLANGE; WALL AND FLANGE 0.100 IN. THK; THREE MTG HOLES 0.523 IN. MIN 0.539 IN. MAX DIA ON 3.400 IN. DIA BOLT CIRCLE"