The big, lightweight aluminum body combines with a heavy stainless steel ring along the perimeter to promote added head stability. The three-piece ('hole seeking material') face insert virtually eliminates energy loss (and distance loss) on off-center hits due to a livelier, higher-rebound polymer in the heel and toe. Typical blade putters, for example, experience as much as 10 percent energy loss on off-center (0.5 inches) hits. In addition, the clubface radius (curvature) is designed to reduce skidding so putts roll sooner with topspin. How? The center of the radius is 0.03 inches higher than the center of the ball, to promote contact with the top half of the ball.