Cleveland CG4 Tour Irons. The new Cleveland CG4 Tour irons combine the benefits of CG2 and CG4 irons to create one of the most versatile sets in golf. These clubs have a shorter blade length than the original CG4 irons, resulting in a compact head for increased workability. Progressive offset throughout the set promotes easy-to-hit long irons with more workability and trajectory control in the short irons. With a thin top-line, the CG4 Tour irons appeal to the better player's eye. Cleveland's goal was to find or create a material that would damp vibration in an unprecedented fashion and could be readily manipulated and engineered for performance. This new metal, while not a composite, is infused with 17 times more carbon than traditional 8620 and 1020 steels. Using a process unique to CMM material, microscopic carbon spheres are infused within the molecular structure of the metal. This creates a matrix that is 10% less dense than ordinary steel yet it maintains the hardness and manipulation properties of cast or forged carbon steel. These density relieving spheres within the CMM metal also dramatically damp vibration offering a pure, soft feel never before achieved in any golf club.