Nike Forged Pro Combo OS are a set of forged carbon steel irons that hold true to the club's heritage while offering a shift toward more forgiveness. The Pro Combo OS Irons deliver excellent feel transmission with the use of soft/forged 1030 carbon steel. Milled flat faces offer predictable distances and shot patterns, as well as full and uniform golf-ball compression. Tests show the landing variance between shots hit with milled and unmilled irons can exceed five yards, or just enough to keep you out of that greenside water hazard. Nike proprietary U/V Scoring Grooves, the perfect blend of square and angled grooves, channel water and grass away from the clubface more effectively, allowing cleaner contact and better control. Three Pro Combo OS designs maximise this set's performance, with Deep Undercut long irons, Full Cavity mid-irons, and Muscle-Cavity short irons. The Pro Combo OS long irons are designed with a deep undercut and wide sole to position the centre of gravity lower and deeper in the clubhead to more efficiently get the ball airborne. The set's Progressive Offset reduces the risk of slicing by allowing an additional split-second to square the face in the long irons, while maintaining a high level of shot-shaping creativity in the mid and short irons. Variable sole widths are wider in the long irons for forgiveness, and reduced throughout the set to maximise versatility. Nike Speed Step Steel constant-weight shafts are made of a unique, high-strength steel alloy manufactured by True Temper that creates a steel shaft 30% lighter than traditional steel shafts. The lightweight and soft-tip shaft encourage greater distance and higher ball flight. Shot-makers get the advantage of Nike's two-step forging process, most-commonly used in high-end blade irons. The clubheads are precision forged to shape, then squeeze forged to align the grain. This meticulous, time-consuming process eliminates soft and hot spots, creating a much more consistent ball-striking surface than those associated with cast or faux-forged irons.