Packing performance-enhancing innovations into a compact profile, the i540 is engineered for golfers seeking added speed and green-holding stopping power in a player-preferred shape. Three key advancements distinguish the i540 from its predecessor, the i530, highlighted by the addition of tungsten weighting along the sole of the four through seven irons. Made possible by a lighter, shallower face, which creates significant weight savings, this design lowers the center of gravity, resulting in increased ball speed and a higher launch angle. The elevated launch is a huge boon, as it generates greater stopping power, making the longer irons in the set much more playable. The second upgrade is the i540's 9% thinner forged, variable-thickness maraging-steel face. The thinner the face, the more flexible it is, and the i540's dramatic reduction in thickness creates metal-wood-like bending, producing measurably faster ball speeds and a higher max apex height. Finally, the i540 adopts PING's patent-pending inR-Air technology. This innovative technology, comprising an air bag strategically positioned behind the face, greatly improves sound and feel, which many found lacking in the i530, without restricting face flexion. The compound of the insert underwent extensive testing and was ultimately selected for its ability to maintain pressurization in any environment or elevation. PING i530 Irons Feature: Player's distance iron designed for speed, distance, a high launch, and playability in a compact footprint Tungsten weighting in 4 to 7 irons lowers the CG for increased ball speed, a higher launch, and more stopping power Forged, variable-thickness maraging-steel face is 9% thinner for more face flexing, faster ball speed, more distance, and a higher max height inR-Air Technology (internal airbag) produces a more desirable sound and feel at impact i-Beam Technology adds structural support and contributes to the improved sound and feel Stock Steel Shaft: True Temper Dynamic Gold