| 摘要 |
PROBLEM TO BE SOLVED: To provide a punching tool which correctly and certainly punches a gypsum board as expected through a simple punching operation. SOLUTION: This punching tool A has a cylindrical shape for opening a hole C in the gypsum board B constituting a wall surface. The cylinder peripheral side part of one open end side 10' of the tool A is constituted of two or more chevron cutting blade parts 20 provided sequentially in a direction in which the cutting blade parts 20 are arranged around the cylinder peripheral side.
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