Abstract: A trailer has a coupling by which it is coupled to a towing vehicle. A coupling comprises two crossed-arms one end of each of which is articulated to the trailer and the other end of which is adapted to be hooked to the towing vehicle. The wheels of the trailer are mounted for swivelling movement about upwardly forwardly inclined pivotal axes; and the horizontal axes of rotation of the wheel are disposed to the rear of these pivotal axes so that the tractor wheels follow the path of the vehicle wheels.

Abstract: Two supporting elements of a stand for a display panel can either be opened-out and placed on the ground in the service position or folded-back when not in use. The ends of the two supporting elements are associated with a pivot on each side of the panel which is thus capable of rotating about a horizontal axis. Springs permit angular displacement of the panel to a horizontal position and serve to return the panel to a substantially vertical rest position. Potential applications of the device include portable traffic signs and advertising panels.