Abstract: An impact absorbing bumper mounting unit for automotive vehicles includes inner and outer nested members of C-shaped configuration. The outer member has a composite shape with one corrugated end portion fixed to a bumper assembly and its other C-shaped section portion adapted for attachment to the vehicle frame. The inner member has a uniform C-shaped section with its one end fixed to the bumper assembly and its other free end spaced from the frame attached end of the outer member. The composite outer member provides an impact absorbing corrugated portion and a C-sectioned guide portion which cooperates with the inner member for controlled coaxial collapse of each mounting unit during a low speed impact obviating damage by the bumper assembly to the body work.