Nike Slingshot. Made from 455 Stainless Steel. Air CG - centre of gravity - is suspended in air beyond the thickness of the face to launch the ball higher and help square the club at impact. 3-D Flow Weighting - Slingback design incrementally shifts the weight higher and towards the toe as club numbers get higher. Progressive Offset - gradually reduced from long to short irons for increased control and shotmaking. Enhanced Consistency - all clubfaces of Nike Slingshots tare Computer milled flat to within .002" and have engraved scoring lines to help ensure consistent and predictable ball flight and spin rates. Wide Sole - the wide constant sole width of the Slingshot irons increases effective bounce to help prevent digging and "fat" shots.