Callaway's Aggressive irons - X Hot Irons
The company's new X Hot irons employ a thinner face design for improved ballspeed. That's not new, but through a unique undercut cavity, the X Hot irons are designed to lower the area of the face that is most flexible in an effort to put it in line with where most iron shot impacts occur: low on the face. Callaway Golf calls its X Hot set "aggressive irons" that produce "measurable distance gains" over previous generation Callaway irons. In the X Hot irons, Callaway takes the "Speed Frame Face Technology" it's been using in its drivers and utilized it in irons. That tech is designed to create a better transfer of energy from clubface to golf ball, thereby boosting ball speed and distance performance.