For the Callaway XR Driver, Callaway worked with experts at Boeing to redefine what's possible with ball speed and aerodynamics. Callaway engineered their most forgiving shape ever and Boeing made it fast with a re-engineered Speed Step Crown. This thing is big and fast like you wouldn't believe, with a high speed head and lower drag in the crown that, as you can guess, is going to add some serious ball speed. It's extremely forgiving from the larger shape for more MOI, a stretched out crown with a bigger footprint, and a Center of Gravity that's lower and deeper. For more ball speed all across the face, Callaway added their next generation R*MOTO face that's lighter and up to 19% thinner. You want the ultimate in ball speed? We’ve got it right here.