Wilson Staff D300 SL Iron Set 5-9, PW, SW, Men, Right Handed Graphite Shaft Regular Mens Right Hand Superlight. 7 Iron. The D300 stands not only for distance, it defines it. The next generation of FLX Face technology allows the club blade to work 76 percent loosened from the rest of the club head. This guarantees maximum flexibility in the meeting moment. The consequence is a powerful tee of the ball. The power holes are filled with TE031 urethane. They produce a distinctive sound and provide an outstanding feel when hitting. In addition, the accuracy of the D300 iron increases. Features FLX FACE TECHNOLOGY: The groundbreaking FLX Face technology minimises the contact points between the thin club blade and the club head. The flexibility of the striking surface is thus maximised. 76 percent of the face have been released from the club head, the contact between both components is only over 24 percent of the striking surface.