Patent ID: 7390271

Claim:
A hollow golf club head comprising a sole portion provided with at least one rib protruding from an inside surface of the sole portion and extending from a toe side to a heel side, wherein the rib is curved in a manner that a toe-side end and a heel-side end of the rib are located closer to a face side than a central part of the rib, and wherein provided that a toe-heel width of the sole portion is A(mm), a face-back width of the rib defined between a point thereof closest to the face side and a rearmost part thereof is B(mm), and a toe-heel width between a toe-side end of the sole portion and the rearmost part of the rib is C(mm), B(mm) is in the range of 20 mm to 60 mm, (B/A) is in the range of 0.2 to 0.5 and (C/A) is in the range of 0.3 to 0.7.