An integral structural element particularly well suited as a component of a body-in-white comprises an elongated hollow member with a first end and a second end opposite thereto. A first region, a second region, and a third region extend between a first end and a second end of the hollow member. A first flange extends substantially the length of the elongated hollow member. A second flange extends substantially the length of the elongated hollow member's first region. A first socket or connecting structure is adapted to receive therein a roof header and is disposed on the elongated hollow member between the first region and the second region. A second socket is adapted to receive therein a B-post disposed on the elongated hollow member between the second region and the third region. This integral structural element is a component of a motor vehicle's body-in-white.