This is known as “energy lensing”, and in the irons energy lensing allows the face to behave more efficiently to promote faster ball speed and distance, dramatically enhancing performance. In fact, it helped raise the COR right up to the limit in each iron. Callaway has never reached that level of speed in a full set.
To develop Epic irons, Callaway pushed themselves in a way that they could elevate performance to the highest level they’ve ever achieved. It had to provide the absolute best combination of ball speed, distance, forgiveness, accuracy, control and feel. And to go beyond that standard, they had to be extremely meticulous, creative and committed to carefully crafting each material.
Callaway has been the #1 Iron in golf since the beginning of 2015. While developing Epic, they started by improving the technologies that made them the category leader. And Callaway's revolutionary 360 Face Cup is the technology that truly led them to #1.