Cobra Fly-Z XL 8-Piece Combo Set Regular Flex. Combines two different cavity designs. Wedges 9i incorporate a traditional undercut design for precision and control for the golfer, while the 8i - 4i feature a duel cavity hollow design that results in a low, back center of gravity enabling the golfer to hit it higher and farther. The combo set, which includes the dual cavity design hollow and cavity back irons, also include three Fly-Z XL Hybrids that deliver exceptional distance, forgiveness and easy up performance. Fly-Z Xl Graphite shafts on the Hybrids and KBS CPI- 1005 Steel on the irons.