US Patent 9220960 Putter head, adjustable shaft and putter

A golf club head comprises a front portion, a rear portion, a toe portion and a heel portion that together form a two-piece body and for which a center of gravity is defined. The body comprises a central portion as a first piece and a frame as a second piece. The frame encloses a substantial portion of the central portion within an XY-plane. The central portion is connected with the frame with fasteners along at least the front portion. The moment inertia of the club head about a z-axis of the center of gravity is between about 7,000 g·cm2 and about 14,000 g·cm2.