Abstract: A non-reusable syringe comprising a syringe body having a lower extremity closed by a base provided with a cone to receive a needle and a shaft terminated by a piston sliding tightly in the syringe body. A resilient flexible plate having a diameter greater than the inner diameter of the syringe body and thus inducing through its curvature a weak frictional force enabling the displacement of the shaft in a first direction and a strong frictional force opposing displacement of the shaft in the other direction is mounted in the shaft. To avoid attempted reuse of the syringe, a zone of weak resistance to breakage by traction is provided on the shaft. This zone break under a traction lower than the strong frictional force, but greater than the weak frictional force.

Abstract: A vehicle is disclosed having a chassis supporting a platform having a network of criss-cross guiding rails. Trolleys circulate along these rails so as to be selectively movable towards the rear of the vehicle for the loading and unloading of road signs. The trolleys are provided with a braking device to enable them to be immobilized on the rails. The vehicle may be a trailer for the transportation of road signs, for example to indicate road works on streets and expressways.