| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a golf club which is classified not depending on the head speed such as a conventional method, but depending on a new index which has not conventionally been found. <P>SOLUTION: This golf club 10 has a golf club shaft 14, a golf club head 12 which is provided on one end of the golf club shaft 14, and an identification mark 20. On the identification mark 20, information for classifying the golf club from a rotational energy amount E of the golf club 10 which rotates in the hitting direction of the golf club 10 right before a golf ball hitting at the time of a golf swing is displayed. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
