The new Big Bertha 2019 irons, combine Callaway's cup-face design with a new internal, multi-material weight system to boost performance. The thin, cup-face design helps spread the sweet spot across a larger portion of the hitting area. Slower-swinging players not only will gain distance on solidly struck shots, they will maintain ball speed more effectively on mis-hits because the face flexes more efficiently at impact. To create a higher launch and further increase forgiveness, Callaway designed each Big Bertha iron with what the company calls a Suspended Energy Core. It is comprised of a uniquely shaped, metal-injection-molded (MIM) internal tungsten weight that pulls the center of gravity lower and away from the face. That promotes higher-flying shots. This results in enhanced ball speed and higher launching shots with better sound and feel. Satisfaction and authenticity are guaranteed. Standard Callaway warranty applies.