US Patent 7510485 Golf club head

A golf club head comprises a main body and a crown cover disposed in a crown portion of the head, wherein the main body comprises a crown base made of a metal material and provided with a plurality of openings gradually decreasing in the opening area from the backside to the foreside of the head, and the crown cover is made of a material such as FRP whose specific gravity is lower than the metal material, and disposed on the crown base so as to cover the openings.