Available in 300M and E4340.Torsional input shaft.Bushing journals and splines are the same diameter and will be precision ground on centers after heat treat.NO UNDERCUTS behind the splines.Both ends of the shaft are identical except for spline count.The whole profile has been redesigned to make this the tuffest and smartest design ever available.Will go out for splining tomorrow and will be in stock shortly.4R100 next..