"MATERIAL ALUMINUM ALLOY CASTING,ALLOY 355-T71; BRINELL HARDNESS 70-90;21 VANES; 20.062 IN. NOMINAL DIA; 2.919 IN. W; 24 HOLES 0.281 IN. DIA,EQUALLY SPACED ON A 8.375 IN. DIA BOLT CIRCLE REF; 40 HOLES 0.406 IN. DIA,EQUALLY SPACED ON A 19.406 IN. DIA BOLT CIRCLE REF;"