To easily remove a pole even when a polygonal body is embedded under snow by disposing the polygonal body in the upper part of a screw body in a pole support body for a slalom and a giant slalom and forming almost the same shaped recessions by which a pair of pins in a setting tool are optionally engaged with the respective side surfaces.

When the pole 100 is embedded under snow, a lower hole being a little smaller than the outer diameter of a cylindrical part 10 is obtained in snow through the use of a drill, the tapered tip part 18 of the cylindrical part 10 is inserted to the lower hole, the pines 53 of the setting tool 50 are engaged with the polygonal recessions of the cylinder 10 and a handle 55 is operated by forward rotation so as to be screwed. When the pole 100 is removed, the setting tool 50 is used so as to operate the handle 55 by backward rotation. Even when the polygonal body is embedded under snow and the positions of the recessions are not recognized visibly, the setting tool 50 is alloted so as to rotate the handle. Then, the pair of pins are easily engaged with one of the recessions. The pins are rarely engaged with the same recessions through the use of repetition so that the durability of the recessions is attained.