Callaway X Series 2019 DriverNEW! 2018 Callaway X Series Driver delivers faster ball speeds with their patended Variable Face Thickness (VFT) technology. VFT technology allows more flex to the clubface and help produce faster ball speeds. The COG (Centre of Gravity) location not only promotes a more consistent ball flight but also increases the stability of the head for better forgiveness and accuracy.Available in 9.5 and 10.5Regular or Stiff Graphite Shafts