“(3) the first semi-trailer has a maximum length of 16.20 m and a minimum length of 12 m, in the case of a B train double, or 13.50 m, in the case of an A or C train double, the whole without taking into account the presence of a flexible folding aerodynamic system located at the rear of the semi-trailer, provided that, as shown,(a) any part of the system located at more than 1.9 m from the ground does not exceed, when unfolded, by more than 152 cm the rear end of the vehicle;
(b) any part of the system located at less than 1.9 m from the ground does not exceed, when unfolded, a virtual line connecting the following points:i. a point located at 1.74 m from the ground and 121 cm from the rear end of the vehicle;
ii. a point located at the rear end and the lowest part of the vehicle bumper or, if there is no bumper, a point located at the lowest part of the rear end of the vehicle;
(c) any part of the system does not exceed, when folded, by more than 30.5 cm the rear end of the vehicle;
“(4) the second semi-trailer has a maximum length of 16.20 m and a minimum length of 12 m, without taking into account the presence of a flexible folding aerodynamic system located at the rear of a road vehicle and complying with subparagraph 3;