Big Bertha is the company's first iron model to incorporate "360-degree face cup" technology. Previously, the face cup was found in woods only. Attaching the stainless steel face to a hollow body allows specific areas of the clubface to be thinner, which lead to more flex and ball speed.
Bertha also has an extra strip of mass that runs heel-to-toe behind the face to shift the center of gravity (CG) low and forward. This weight placement directs more energy into the ball for added speed. According to Callaway, the combination of a hollow body, a hotter face, and low CG should produce shots that fly 1 to 1.5 clubs further than usual.
The new Bertha is built for the masses so single-digit handicappers would be wise to look elsewhere. Available 4-iron through SW in True Temper Speed Step 80 steel or UST Recoil graphite shafts. Available October 17. $1,000, steel; $1,200, graphite.