Abstract: A golf club putter including a putter head with a curved bottom surface, a front face with a full-face cavity, an adapter molded into the full-face cavity, and a back surface with a weight-reducing cavity formed therein. The volumes of the full-face and weight reducing cavities are substantially equal to keep the putter head relatively balanced. The adapter is made of a polyurethane material with a hardness of at least Shore A 90 durometer. The inside surface of the adapter is mechanically or adhesively bonded to the inside surface of the full-face cavity thereby enabling the entire energy of impact when a ball is struck to be transmitted throughout the putter head, thereby providing a softer felling to the user. The front and back cavities reduce the mass along the central, transverse axis of the putter head, thereby decreasing the torque about the shaft, which enables the user to more easily maintain the front face in a perpendicularly aligned position during the swing.