"MATERIAL:IRON CASTING,GRAY CLASS 40 ALTERNATE CAST IRON SAE 121;MATERIAL HARDNESS BRINELL MIN 179 TO MAX 241 OD MIN 20.242 IN. TO MAX 20.246 IN.;IDMIN 17.950 IN. TO MAX 17.960 IN.;PD 18.000 IN.;W MIN 2.003 IN. TO MAX 2.005 IN.;INTERNAL SPLINE DATA: 5 PITCH SPECIAL 30 TEETH ON BASIS OF 90 10 DEGREE PRESSURE ANGLE;MOUNTING HOLES QTY 30 0.438 IN. DIA THRU COUNTER BORE 0.688 IN. DIA TO DEEPTH OF 0.440 IN."