Callaway combines a light-weight triaxial crown with a titanium Exo-Cage to create the extremely forgiving Big Bertha Fusion driver. Using these elements allows the designers to place the saved weight around the head to create the forgiveness.
The Big Bertha Fusion driver also has a unique head shape. The shape makes the head more aerodynamic, increasing clubhead speed and distance. The head shape moves the CG back and towards the perimeter to create more forgiveness.
The crown of the Big Bertha Fusion driver has Speed Step technology. This aerodynamic feature reduces drag throughout the swing to increase swing speed.
Read more about the Big Bertha Fusion driver here.