US Patent 7455597 Golf club head

This invention provides a hollow golf club head having a face portion, a crown portion, a sole portion, and a side portion. The head has 0.3 to 0.6-mm thick thin-walled regions on the face side of the crown portion and the face side of the side portion, a medium-thick-walled region thicker than the thin-walled region of the crown portion at the back of the thin-walled region, and a high-rigidity region on the face side of the sole portion.