The U-shaped adapter (1) is fastened to the top of the backrest of a front seat in a road vehicle. It has holes and gripping slots (6) in the sides (16,17) of the U-shape to accommodate rods supporting the headrest. The U-shaped adapter is double- walled with the walls joined on the outside of the U-shape to form a U- section. There are cutouts at the sides holding the rods for the headrest. A locking latch (2) and a clamping element (3) for holding a briefcase are fitted in the center of the base of the U-shape.
