"STEEL; 3.188 IN. OD; 1.594 IN. O/A LG; INVOLUTE SPLINED BORE,37 TEETH,16/32 DIAMETRAL PITCH,2.3125 IN. PITCH DIA; INVOLUTE EXTERNAL SPLINES,50 TEETH,16/32 DIAMETRAL PITCH,3.125 IN. PITCH DIA; INCLUDES SHIFTING GROOVE 0.325 IN. W BY 2.730 IN. ROOT DIA"