Wilson Staff D9 Golf Irons Steel The new Wilson Staff D9 Golf irons and a huge step forwards in the design of game improvement distance irons. Wilson used a revolutionary approach to iron design when creating the D9 irons and a generative process saw them design and test hundreds of differing D9 head shapes and Power Hole configurations in the pursuit of increased performance. The result is a high performance game improvement iron that has the potential to take your golf to the next level. The urethane power-holes have been strategically positioned to allow for the club-face to flex at impact and leads to much improved ball speeds and a significant increase in the size of the sweet-spot. This will be music to the ears of golfers who often...