Guerin Rife Island Series Barbados Belly Putter:

The Island Series Barbados Belly Putter features Guerin Rife's RollGrooves technology of horizontal, very closely spaced grooves. The space between the grooves is called land. Because this land is sharp, the ball tends to spend more time on the face at impact. This allows for only one to two degrees of loft instead of the four degrees on conventional flat-faced putters. The grip and lift from the grooves combined with very little loft allow the ball to fall into an immediate roll.