Cleveland Golf 588 TT Iron Set Engineered for tour trajectory; Constant blade height with progressive blade length promotes more forgiveness in long irons and controlled, penetrating trajectory in short irons Engineered undercut modest cavity back with engineered undercut improves ball speed and accuracy on off center hits Face forged technology; Every iron has a forged club face to enhance ball speed and feel Vibration dampening; Multi material iron plaque of polymer and aluminum dampens vibration at impact for more consistent feel Fully customizable; Part of the 588 Irons Family, tour trajectory Irons can be easily interchanged with 588 mid trajectory and altitude Irons to customize a set with the perfect combination of ball flight, feel and forgiveness