Besides the Cobra SSI wedge, Cobra offers a whole lineup of incredible irons to help you step up your game. One of the newest and most innovative lines are the transition design 3400 I/XH irons. They get their name because of their transition design, meaning the clubs have different functional shapes as you move from club to club. The low irons (3 to 7) have hollow backs, for instance, while the high irons (8 to wedge) have cavity backs. These clubs are by far the most engineering clubs manufactured by Cobra, or perhaps by anybody else in the business for that matter.