Abstract: An object is to provide an iron golf club head that has high drainage performance and facilitates application of backspin also in a wet state. In an iron golf club head including a plurality of scorelines in a face surface, a microgroove including at least an inclined groove is included between the scorelines, the microgroove extending in a heel leading edge-toe top edge direction to be connected to an upper scoreline.

Abstract: A swing analysis device for analyzing a swing of a user of a golf club accepts input of acceleration information, angular rate information, and strain information of a shaft of the golf club, detected by a sensor attached to the shaft, calculates attitude information of the golf club in a swing period, based on the acceleration information and the angular rate information, corrects the attitude information of the golf club at impact, based on the strain information of the shaft, and displays the corrected attitude information of the golf club on a display.

Abstract: An object is to provide an iron golf club head that has high drainage performance and facilitates application of backspin also in a wet state. In an iron golf club head including a plurality of scorelines in a face surface, a microgroove including at least an inclined groove is included between the scorelines, the microgroove extending in a heel leading edge-toe top edge direction to be connected to an upper scoreline.

Abstract: A swing analysis device for analyzing a swing of a user of a golf club accepts input of acceleration information, angular rate information, and strain information of a shaft of the golf club, detected by a sensor attached to the shaft, calculates attitude information of the golf club in a swing period, based on the acceleration information and the angular rate information, corrects the attitude information of the golf club at impact, based on the strain information of the shaft, and displays the corrected attitude information of the golf club on a display.

Abstract: An iron golf club head includes: a face portion including a ball striking surface and a first reverse surface; and a sole back portion including a second reverse surface connected with the first reverse surface and located below the first reverse surface. The iron golf club head has a first hollow separated from outside by the face portion and the sole back portion. The ratio W/V1 of the weight W (unit: g) of the iron golf club head relative to the volume V1 (unit: mm3) of the iron golf club head is 6.5×10?3 or less. The sole maximum projected width Sw of the iron golf club head is 25 mm or more. The sweet spot height Sh of the iron golf club head is 20 mm or more.

Abstract: A golf ball includes a land portion, and a plurality of dimples configured to be recessed from the land portion. Each of the plurality of dimples includes a circular bottom face, a circular opening configured to have a larger diameter than the bottom face, and a side face configured to connect the bottom face and the opening. The side face is configured to be linearly inclined so that the diameter of each of the plurality of dimples increases from the bottom face toward the opening. The diameter of the bottom face is 0.45 mm or more and 0.60 mm or less.

Abstract: An iron golf club head includes: a face portion including a ball striking surface and a first reverse surface; and a sole back portion including a second reverse surface connected with the first reverse surface and located below the first reverse surface. The iron golf club head has a first hollow separated from outside by the face portion and the sole back portion. The ratio W/V1 of the weight W (unit: g) of the iron golf club head relative to the volume V1 (unit: mm3) of the iron golf club head is 6.5×10?3 or less. The sole maximum projected width Sw of the iron golf club head is 25 mm or more. The sweet spot height Sh of the iron golf club head is 20 mm or more.