US Patent 7588503 Multi-piece golf club head with improved inertia

A multi-piece iron-type golf club head with a substantial weight member is disclosed and claimed. The golf club head includes a plurality of body members. A first body member includes a face, a rear surface, and a hosel. A viscoelastic material is attached to the rear surface, and a second body member is attached to the viscoelastic material. The second body member, which may be a weight member, has a substantially larger mass than in known golf clubs. The viscoelastic member may form a substantial part of the club head. The club head may also have a recess located in a top portion thereof between the heel and the toe and extending toward the sole. A low-density insert may be positioned within the recess.