a structural part for a motor vehicle includes an inner component having a generally rectangular cross section and configured in the form of a multichamber hollow section made of light metal , and an outer component having a generally rectangular cross section . the inner and outer components are movable in a telescoping manner relative to one another between an idle state and an activated state . a first locking mechanism is provided to lock the idle state and a second locking mechanism is provided to lock the activated state . the movement of the inner and outer components from the idle state to the activated state is hereby realized by an actuator .