X-Series Irons from Callaway Golf have been long favored by some of the best players in the world because of their performance-enhancing technologies and by recreational golfers due to their forgiveness and great looks. The new X-18 Irons combine many of the same patented Callaway Golf core technologies used in earlier X-Series models with a new traditional head shape and size, and high-polish finish. The X-series legacy of performance continues.