| 摘要 |
PURPOSE: A baseball bat is provided to minimize air resistance to the surface of the baseball bat and friction area. CONSTITUTION: A baseball bat is constituted as follows. A plurality of wrinkles is formed on the surface of the baseball bat by forming a plurality of mountains(114) and valleys(116). The wrinkle is formed in a spiral shape. A receiving unit accepting contents is formed inside a striking unit of the baseball bat. A cover layer is formed on one surface of a handle unit or a hitting unit. |
