Stiff Flex. The XXIO X fairway wood combines True-Focus technology and advanced construction for an easier to hit, higher launching, and longer flying wood. The Hi-Energy Impact Head design is built with a thin, variable face that enlarges the size of the sweet spot to improve the consistency of your swing. Cup face construction allows the perimeter to be thinner, saving weight and transferring more energy to the ball for more distance and the Sole Channel compresses on low-heel impacts for higher ball speed.