The Callaway Big Bertha irons for women feature a hollow body construction with a 360 cup face of the sort they’ve used for some time on their metal woods and drivers. The result, Callaway says, is a maximum forgiveness and distance.
The clubs’ soles are progressive, with a wider design in the long irons and more narrow in the short irons. Inside, there’s a thing Callaway calls a “standing wave,” which distributes the weight low and to the perimeter for high moment of inertia and high launch.
In spite of the hollow body, the Big Bertha Women’s irons ae apparently not really hybrids, because you can get a full set of these hollow body irons, or mixed with Big Bertha adjustable hybrids.