Designed and manufactured in accordance with, and certified under, the Regulations of the International Federation (IAAF Certificate E-99-0123). The supporting structure consists of 7 extruded aluminium vertical poles with a 150 mm diameter octagonal section, reinforced by internal ribs. The upper end of the poles is L-shaped. The joint between the vertical and horizontal part is internally reinforced through a steel structure. A 1000 mm long square-section upright protrudes from the bottom of each pole to be inserted into the foundation. The poles have two different heights, 7.5 and 10.5 m, to hang the safety net at the legal heights, which are respectively 7 m and 10 m. A hinge at the bottom of each pole facilitates the installation. Each pole is equipped with a winch to manually activate the lifting system of the structure supporting the safety net. The structure supporting the net is made from 80 x 80 mm square section extruded aluminium ribbed profiles and consists of 9 sections internally reinforced by a 50 x 50 mm square section steel tube. The bottom side of these profiles is equipped with a groove to hang the safety net. The top side is provided with eyelets to connect the snap hooks that lift the structure. At the bottom of the net a steel structure acts as a weight to stretch the net into the legal position and shape. The supporting structure is equipped with two rectangular doors, made of two 80 x 80 mm square section extruded aluminium profiles, internally reinforced in each individual junction through a steel structure. Each door is equipped with two winches to lift the structure supporting the net.