Complete Sellection: XXIO 2016 Driver XXIO9 MEN (Left or Right) (8.5, 9.5,10.5 or 11.5)(Regular,Stiff or RS) bundle with+ 2 Callaway Balls Bundle includes one XXIO9 Driver and two Callaway Golf Balls Dual Speed Technology maximizes the power of the golfer's swing to achieve higher clubhead speed and higher ball speed. Heavier clubhead increases kinetic energy at impact for more distance Thinner material in the face periphery delivers improved repulsion performance over the entire face Center of gravity (CG) is positioned closer to the heel, for improved repulsion performance near the heel