The Callaway Great Big Bertha Epic Sub Zero driver represents a true paradigm shift towards a low-spinning driver that is also forgiving. The high-speed/low-spin combination that many tour players seek come from Callaway�s innovative Jailbreak Technology, which positions two ultra-light titanium bars behind the face to promote faster ball speeds over the entire club face. It�s forgiveness is thanks to a multi-material construction that combines a titanium Exo-Cage with triaxial carbon crown and sole panels for a lightweight club head that accounts for 50% of the head�s surface. The Epic Sub Zero�s unique club head design places the CG low and deep in the club head to promote high launch and low spin.