Patent ID: 7717806

Claim:
A putter head comprising: a face member formed of a material having a specific gravity of 2.7 to 8.0; an intermediate member formed of a material having a specific gravity of 0.9 to 3.0; and a back member formed of a material having a specific gravity of 8.0 to 19.2, wherein a moment of inertia, IY, about the center of gravity is such that IY≧4000 g·cm 2 , and a relationship between a head length L and a head width W is 0.7×L≦W≦L, wherein the intermediate member includes an upper member and a sole member, the upper member and the sole member forming an opening with two ends, wherein one end of the opening is closed by face member, and the other end of the opening is closed by the back member.