| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a putter developed so that a ball advances in the target direction even if the golf ball misses a sweet spot of a putter. SOLUTION: A concave putter is constituted so that a vertical directional ball hitting surface 1 of the putter is formed into a straight surface and a horizontal directional ball hitting surface is formed into a concave.</p> |
