Patent ID: 7500925

Claim:
A golf club comprising a hollow golf club head which has a face portion for striking a golf ball, a crown portion connected to the face portion, a sole portion connected to the face portion and a side portion connected to the face portion, the crown portion and the sole portion, wherein: a first region whose surface area constitutes 5% or more of a total surface area of the crown portion is formed by a first outer shell member in a region of the crown portion which is located along a connecting edge of the crown portion connecting to the face portion and within a distance of 50 mm from the connecting edge, and a second region whose surface area constitutes 5% or more of the total surface area of the sole portion is formed by a second outer shell member in a region of the sole portion which is located along a connecting edge of the sole portion connecting to the face portion and within a distance of 50 mm from the connecting edge of the sole portion, the first outer shell member structured by a carbon fiber reinforced plastic material and the second outer shell member structured by a metal alloy; and when an product of an elastic modulus of the first outer shell member in a direction in which a striking surface is oriented and a thickness of the first outer shell member in the first region is taken as a first equivalent rigidity and a product of an elastic modulus of the second outer shell member in the direction in which the striking surface is oriented and a thickness of the second outer shell member in the second region is taken as a second equivalent rigidity, a ratio of either the lower of the first equivalent rigidity and the second equivalent rigidity to the higher is equal to or less than 0.75, wherein a side member of the side portion has an edge which is bent to a side of the crown portion to provide an extension portion extending in the crown portion to form a part thereof, wherein a face member of the face portion has an edge which is bent to a side of the crown portion to provide an extension portion extending in the crown portion to form a part thereof, and wherein the first outer shell member is joined to the extension portions from an outside of a hollow region formed by the face portion, the crown portion, the side portion and the sole portion.