Open-profile beam composed of two shells for a bumper

The invention relates to a bumper for a motor vehicle with a transverse beam (2) that can be fixed transversely to the longitudinal members of the motor vehicle frame with the incorporation of impact dampers (3). The transverse beam is formed as a profile open toward the impact dampers (3) from an upper shell (5) and a lower shell (6). To the upper longitudinal edge (7) and to the lower longitudinal edge (8) of the front web (9) of the transverse beam (2), a rearward-directed leg (10) is adjoined in each case. This is designed as a deformation fold with an obliquely extending length section (11), which is adjoined by a substantially vertically aligned vertical section (12). This transitions at its end into a reinforcing flange (13) extending at approximately right angles to this.