Matl steel per ams 6260; hardness per rockwell c30 min and c40 max; 0.396 in. Min and 0.400 in. Max long; 6.621 in. Min and 6.622 in. Max od; bore splined 69 teeth at 4.9286 pitch dia; 16 circular notches at 0.328 in. Radius; od grooved to 5.562 in. Diameter for 0.095 in.