The support beam (9) is in the form of a hollow profile such as a tube. The front bumper is mounted on the front end of the beam. The wall thickness of the profile varies so that it is thinnest at the front end of the profile where the bumper is attached and gradually increases in thickness. The variation in thickness ensures that during a head-on collision the resistance against crumpling-up of the profile increases the further back the front end is pushed. The gradual increase of thickness of the wall is achieved during mfr. by applying high pressure to the inside of the profile.
