Wilson Staff Mens Di11 Distance Irons #4 - Pw True Temper Steel Wilson Staff Di11 A modified exoskeleton moves weight low to promote a higher ball flight, and back away from the face for greater head stability and straighter ball flight. 85% of all shots are struck from the center of the toe to the club. Wilson's patented wide-tip shaft technology negates the twisting on off-center hits to promote a straighter ball flight. A coating of lightweight elastomer to dampen vibration on off-center hits