Abstract: A metal wood club head of a hollow hull structure according to the present invention is such that the vertical difference between a maximum face part height (MFH) from a sole part (4) and a back part height (BH) from the sole part (4) is at least within 25 mm, the height of a crown part (3) having a width of 30% to 70% of a head width from the sole part (4) is substantially identical to the maximum face part height (MFH) or more than that, the vertical difference between a maximum crown part height (MCH) from the sole part (4) and the maximum face part height (MFH) is at least within 8 mm, and the radius (R1) of curvature of the crown part (3) is substantially uniformly within the range of 100 mm to 1000 mm, while it sets the radius (R2) of curvature of the sole part (4) substantially uniformly within the range of 500 mm to 2000 mm, and sets the ratio of thicknesses of the crown part (3) and the sole part (4) within the range of 1.0 to 1.2.

Abstract: A groove is provided a surface on a cavity portion side of a sole portion in a head portion of an iron golf club, and a thickness of a ball hitting portion in a face portion is made larger than a thickness of a top edge side portion of the face portion and at least as large as a thickness of a sole side portion of the face portion. In a golf club set according to the present invention, the groove has the greatest depth in a long iron golf club, while the groove has the smallest depth in a short iron golf club or no groove is provided in the short iron golf club.

Abstract: A core (3) for a caddie bag includes three arc portions (31 to 33) each with a PCCP structure. These arc portions are connected by a hinge portion (34) without the PCCP structure, and the hinge portion is bent to form a cylindrical core. The cylindrical core has one end with a collar (5) attached thereto, and the other end with a bottom member (6) attached thereto. The collar and the bottom member are connected by a frame member (12), whereby a caddie bag (1) is constructed.

Abstract: The inventive iron golf club comprises a head part having a face, and a restitution coefficient is in the range of at least 0.81 and not more than 0.95 when colliding a ball against a sweet spot in the face at a speed of 44 m/s. In the aforementioned iron golf club, the effective face area of the head part is at least 2500 mm2 and not more than 5000 mm2, the effective deflection length is at least 36 mm and not more than 72 mm, and the thickness of the face is at least 1.0 mm and not more than 2.5 mm at the sweet spot.

Abstract: The inventive golf club comprises a head of a metal having a face and a flexural range, defined in the face, where the quantity of flexure in a direction perpendicular to the face is at least 45% of the maximum quantity of vertical flexure of the face. The flexural range is arranged in coincidence with a hitting spot distribution range of a player in the face. Alternatively, a flexural range having a spring constant of at least 2 kN/mm and not more than 4 kN/mm is present in the face of the inventive golf club.