Variable headrest for seats built-in transversely to the vehicle's direction

The head rest has an arrangement of protective elements fixed relative to the vehicle above and associated with a seat fixed to the vehicle. The head rest consists of a mounting frame (10) fixed to the vehicle at head height, two movable side panels (3) and adaptive cushioning (1,7). The side panels are fixed in the mounting frame and can be folded between a functional position and a standby position.